Our Pick: CVault

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The Best Stash Jars (2026): Humidity-Control, UV-Glass & Smell-Proof

The right jar keeps your flower fresh, potent, and quiet for months. The definitive list — 14 picks across humidity-control, UV-blocking glass, vacuum-seal, and smell-proof, in every size.

By Justin Park · ~13 min read · Updated 2026-06-27

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Our top picks

How you store your flower decides how it smokes weeks later. Light, air, heat, and the wrong humidity quietly degrade cannabis — drying it out, harshening the smoke, and burning off the terpenes that give it flavor and effect. A good stash jar fixes all of it: an airtight, light-blocking container, ideally with humidity control, keeps your flower as fresh, potent, and aromatic as the day you got it (and keeps the smell locked in).

This is the definitive list — 14 picks across every type and size. We've sorted them by what they do: humidity-control (the gold standard, like CVault), UV-blocking glass (blocks the light that degrades flower), vacuum-seal and pop-top (portable and airtight), and smell-proof options — from a 1/8-oz pocket jar to a curing-size canister. Every pick links to its current Amazon listing.

The short version

  • Our overall pick is the CVault — a stainless, airtight, light-proof container with a slot for a Boveda humidity pack, the closest thing to perfect storage.
  • Humidity control is the upgrade: a two-way pack (Boveda 62%) holds flower at its ideal moisture, keeping it from drying out or getting too damp. Add one to any jar.
  • UV-blocking glass (Infinity Jars) stops the light that degrades cannabinoids and terpenes — the cheap clear-glass alternative to opaque metal.
  • Size to your stash: a 1/8–1/4 oz jar for pocket carry, ~1 oz for everyday, and a curing-size canister for larger amounts or home grows.
  • Airtight is non-negotiable for both freshness and smell — pair your jar with a smell-proof bag for travel.
JarBest forTypeSize
CVault MediumBest overallHumidity metal~1 oz
CVault Starter KitBest kit (w/ Boveda)Humidity metal~1 oz
CVault LargeBest for curingHumidity metal~2 oz
CVault 1/4 oz TwistBest small humidityHumidity metal1/4 oz
Boveda 62% PacksBest humidity add-onHumidity packAny jar
Herb Guard All-in-OneBest complete glassGlass + pack1/2 oz
Infinity Jars UV (500ml)Best UV glassUV glassMedium
Infinity Jars 1L UVBest large UVUV glassLarge
UV Glass Stash JarBest value UVUV glassSmall
Tightvac AirtightBest vacuum-sealVacuum pop1–6 oz
Pop-Top Bottles (12pk)Best pocket / multiPop-topDram
Blue Bus BUNKERBest budget smell-proofSmell-proofSmall
Smell-Proof Humidity JarBest smell + humiditySmell-proof1/2 oz
Ball Mason JarBest classic / cheapGlassPint

All 14 picks at a glance — grouped by type

The Stash Jars quiz

Which one should you actually buy?

Skip the scrolling and the second-guessing — answer a few quick questions and we'll match you to your perfect pick, based on how you'll actually use it.

Stash Jars quiz

Question 1 of 3

What matters most?

Tap an answer to continue
Matching from 14 tested picks:CVaultCVaultCVaultCVaultBoveda

💡 Good to know

Our overall pick is the CVault — a stainless, airtight, light-proof container with a slot for a Boveda humidity pack, the closest thing to perfect storage.

01 · Best Overall

Our Pick
CVault Medium Stainless Storage Container

CVault Medium Stainless Storage Container

4.8~$24–$30

Airtight, light-proof stainless steel with a built-in slot for a Boveda humidity pack.

Pros

  • Airtight + light-proof
  • Boveda humidity holder
  • Durable stainless
  • The storage gold standard

Cons

  • Pack sold separately
  • Can't see inside

Bottom line: The gold standard of storage. The CVault combines an airtight, fully light-proof stainless body with a built-in holder for a Boveda humidity pack — so your flower is protected from air, light, and bad humidity all at once. The closest thing to perfect storage, and our overall pick.

Key details: Food-grade stainless steel; airtight silicone-sealed lid; fully light-proof; holder for a Boveda 2-way pack; ~1 oz.

CVault solves every storage problem in one container. The stainless steel is completely light-proof (light degrades cannabinoids), the silicone-sealed lid is genuinely airtight (keeping flower fresh and smell in), and a clip inside holds a Boveda two-way humidity pack against the lid — so your flower stays at its ideal moisture without the pack touching it. Air, light, and humidity, all handled.

Why two-way humidity control matters: a Boveda pack both adds and removes moisture to hold a set humidity (62% is ideal for flower). Too dry and your flower turns harsh and dusty; too damp and it risks mold. A two-way pack keeps it in the perfect window for months — the single biggest upgrade to storage.
Material
Stainless steel
Seal
Airtight silicone
Light
Fully blocked
Humidity
Boveda holder

Who should buy it: Buy this if you want the best all-around storage — airtight, light-proof, and humidity-controlled in one.

What we don't like: You add the Boveda pack separately (or get the kit), and metal hides your flower from view.

02 · Best Kit (with Boveda)

CVault Personal Storage Starter Kit (with Boveda)

CVault Personal Storage Starter Kit (with Boveda)

4.7~$32–$45

The CVault container with a Boveda humidity pack included — complete storage out of the box.

Pros

  • Boveda pack included
  • Complete out of the box
  • Airtight + light-proof
  • Best value as a set

Cons

  • Costs more than container only
  • Metal hides flower

Bottom line: The complete CVault. This bundles the airtight, light-proof CVault container with the Boveda 62% pack already included — so you get perfect humidity-controlled storage out of the box, with nothing else to buy. The easiest way to get the full setup.

Key details: CVault stainless container + Boveda 62% two-way pack included; airtight + light-proof; ready to use.

Everything you need, in one box. Instead of buying the CVault and a Boveda pack separately, this kit includes both — so you open it, drop in your flower, and it's already at ideal humidity, light-proof, and airtight. The simplest path to the best storage there is.

Includes
Container + Boveda
Seal
Airtight
Light
Blocked
Best
Complete setup

Who should buy it: Buy this if you want the complete CVault setup — container plus humidity pack — in one purchase.

What we don't like: Slightly more than the container alone (but cheaper than buying both separately).

03 · Best for Curing

CVault Large (2 oz) Storage Container

CVault Large (2 oz) Storage Container

4.8~$30–$42

The bigger CVault for larger stashes — or for curing your own harvest.

Pros

  • Bigger 2 oz capacity
  • Great for curing
  • Airtight + light-proof
  • Humidity-controlled

Cons

  • Too big for a little stash
  • Pack separate

Bottom line: The big-batch CVault. The Large holds about 2 ounces with the same airtight, light-proof, humidity-controlled design — making it ideal for a bigger stash or for curing a home-grown harvest, where steady humidity is everything.

Key details: Stainless steel; ~2 oz capacity; airtight + light-proof; Boveda holder; ideal for curing.

For more flower, or for curing your own. The Large CVault scales up the gold-standard storage to ~2 oz, which is perfect if you keep more on hand or grow your own — curing harvested flower in a humidity-controlled container is how you develop smooth, flavorful buds. Same airtight, light-proof body, bigger capacity.

Material
Stainless
Size
~2 oz
Use
Storage / curing
Humidity
Boveda holder

Who should buy it: Buy this if you store larger amounts or want to cure a home-grown harvest properly.

What we don't like: Overkill for a small personal stash; pack still sold separately.

04 · Best Small Humidity

CVault 1/4 oz Twist Top Container

CVault 1/4 oz Twist Top Container

4.6~$14–$20

A pocket-size humidity-controlled CVault with a quick twist-top lid.

Pros

  • Pocket-sized
  • Airtight + light-proof
  • Quick twist lid
  • Humidity-compatible

Cons

  • Small capacity
  • Wants a mini pack

Bottom line: The pocket CVault. This 1/4-oz twist-top brings CVault's airtight, light-proof, humidity-controlled storage down to a pocket size — perfect for carrying a personal amount fresh and discreet. Same protection, travel-ready.

Key details: Stainless steel; ~1/4 oz; twist-top lid; airtight + light-proof; mini Boveda compatible.

CVault quality, pocket-sized. The twist-top 1/4 oz is the grab-and-go CVault — airtight, light-proof, and compatible with a mini Boveda pack, in a size that disappears in a pocket or bag. The pick for keeping a personal amount fresh on the move.

Material
Stainless
Size
1/4 oz
Lid
Twist-top
Light
Blocked

Who should buy it: Buy this if you want pocket-size, humidity-controlled storage for a personal amount.

What we don't like: Small capacity, and you'll want a mini Boveda pack to match.

05 · Best Humidity Add-On

Boveda 62% Humidity Packs (8g, 10-Pack)

Boveda 62% Humidity Packs (8g, 10-Pack)

4.8~$10–$18

Drop one in any jar to hold your flower at its ideal 62% humidity for months.

Pros

  • Works in any airtight jar
  • Holds ideal 62% RH
  • Industry standard
  • Cheap, huge impact

Cons

  • Eventually needs replacing
  • Needs an airtight jar

Bottom line: The upgrade for any jar. Boveda packs are the two-way humidity standard — drop one into any airtight jar and it holds your flower at the ideal 62% humidity, adding or removing moisture as needed. The cheapest, most effective upgrade to storage you already own.

Key details: Two-way 62% RH humidity packs; 8-gram size; 10-count; works in any airtight jar; the industry humidity standard.

Turn any jar into humidity-controlled storage. A Boveda 62% pack maintains the perfect moisture level for flower — it releases moisture if the air is too dry and absorbs it if too damp, keeping your stash from going harsh or risking mold. Toss one in a mason jar, a UV jar, or a CVault and you've upgraded your whole setup. The 8g size suits jars up to ~1 oz; the 10-pack lasts ages.

Type
2-way humidity
RH
62%
Size
8g
Pack
10

Who should buy it: Buy these to add humidity control to any jar you already own — the highest-impact, lowest-cost upgrade.

What we don't like: Packs eventually dry out and need replacing (every few months), and they don't make a jar airtight on their own.

06 · Best Complete Glass

Herb Guard All-in-One Smell-Proof Jar

Herb Guard All-in-One Smell-Proof Jar

4.6~$15–$25

A smell-proof glass jar that comes with a humidity pack and a scoop card.

Pros

  • Complete kit included
  • Smell-proof glass
  • See your flower
  • Humidity pack + scoop

Cons

  • Less discreet (glass)
  • More fragile

Bottom line: The complete glass kit. Herb Guard bundles an airtight, smell-proof glass jar with a humidity pack and a scoop card — a full storage solution in one buy, in glass so you can see your flower. The best all-in-one for those who prefer glass to metal.

Key details: Airtight smell-proof glass jar; included humidity pack; smell-proof bag + scoop card; complete kit; ~1/2 oz.

A glass jar that comes with everything. Herb Guard pairs an airtight, UV-tinted smell-proof glass jar with a humidity pack to keep flower fresh and a scoop card for easy handling, often with a smell-proof bag too. It's the complete kit for people who like seeing their stash through glass rather than hiding it in metal.

Material
Glass
Includes
Pack + scoop
Seal
Airtight smell-proof
Size
~1/2 oz

Who should buy it: Buy this if you want a complete, smell-proof glass storage kit with humidity control included.

What we don't like: Glass shows the flower (less discreet) and is more fragile than metal; ~1/2 oz size.

07 · Best UV Glass

Infinity Jars UV Glass Jar (500ml)

Infinity Jars UV Glass Jar (500ml)

4.7~$20–$35

Premium black-violet glass that blocks the light that degrades your flower.

Pros

  • Blocks degrading light
  • Premium black-violet glass
  • Airtight screw-top
  • Best UV glass

Cons

  • Pricier than clear glass
  • Add a humidity pack

Bottom line: The premium UV pick. Infinity Jars use a special black-violet glass that blocks the visible and UV light that degrades cannabinoids and terpenes — giving you the light protection of metal while still being a beautiful, screw-top glass jar. The best UV glass you can buy.

Key details: Ultraviolet (black-violet) glass; airtight screw-top; blocks visible + UV light; premium build; 500ml.

Light is cannabis's enemy, and this glass blocks it. Infinity Jars' ultraviolet glass appears nearly black but lets through only a tiny beneficial spectrum, blocking the light that breaks down your flower over time. Combined with an airtight screw-top, it's premium, light-proof glass storage — the elegant alternative to opaque metal. The 500ml suits a medium stash.

Why UV glass over clear glass: a clear mason jar is airtight but lets in light, which degrades cannabinoids and terpenes over weeks. UV (black-violet) glass blocks that light like metal does, but you still get a premium glass jar. If you want glass, make it UV.
Material
UV glass
Light
Blocked
Seal
Airtight screw
Size
500ml

Who should buy it: Buy this if you want premium, light-blocking glass storage that looks as good as it works.

What we don't like: Pricier than clear glass, and add a Boveda pack for humidity control.

08 · Best Large UV

Infinity Jars 1L UV Canister

Infinity Jars 1L UV Canister

4.7~$30–$45

A liter-size UV glass canister for a big stash — or a home harvest.

Pros

  • Large light-blocking jar
  • Great for bulk / curing
  • Airtight
  • Premium UV glass

Cons

  • Large + pricey
  • Wants multiple packs

Bottom line: The big UV jar. Infinity Jars' 1-liter canister brings the same light-blocking ultraviolet glass to a large capacity — ideal for a big supply, sharing storage, or curing a home grow while keeping degrading light out. The large-stash UV pick.

Key details: 1L ultraviolet glass canister; airtight lid; blocks light; large capacity for bulk storage or curing.

UV protection at scale. For a larger stash or a home harvest, the 1L Infinity Jar holds a lot while blocking the light that breaks flower down — so even a big supply stays fresh and potent. Pair it with a couple of Boveda packs for full humidity control over the larger volume.

Material
UV glass
Size
1L
Light
Blocked
Use
Bulk / curing

Who should buy it: Buy this if you store a large amount or cure your own and want light-blocking UV glass.

What we don't like: Big and premium-priced; needs a couple of humidity packs for the volume.

09 · Best Value UV

UV Glass Stash Jar (Airtight)

UV Glass Stash Jar (Airtight)

4.4~$12–$20

Light-blocking UV glass and an airtight lid at a budget price.

Pros

  • Blocks light
  • Airtight
  • Budget price
  • Effective UV protection

Cons

  • Not premium build
  • Small + add pack

Bottom line: The budget UV jar. This gives you the key benefits — UV-tinted glass that blocks degrading light and an airtight lid — at a fraction of premium-brand pricing. The smart-value way to get light-protected glass storage.

Key details: UV-tinted glass; airtight lid; blocks light; small size; the value UV option.

Light protection without the premium price. A UV-tinted airtight glass jar covers the essentials — it keeps air and degrading light away from your flower — at a budget price. Not as deeply tinted or premium as Infinity Jars, but a genuinely effective, affordable UV option. Add a Boveda pack for humidity.

Material
UV glass
Light
Blocked
Seal
Airtight
Value
Best UV value

Who should buy it: Buy this if you want light-blocking UV glass storage at the lowest price.

What we don't like: Tint and build aren't premium-grade; small size; add a humidity pack.

10 · Best Vacuum-Seal

Tightvac Airtight Vacuum Container

Tightvac Airtight Vacuum Container

4.6~$8–$16

A patented squeeze-to-vacuum container that's airtight, light-blocking, and smell-proof.

Pros

  • Vacuum-tight seal
  • Smell-proof + opaque
  • Compact + cheap
  • Multiple sizes

Cons

  • No humidity control
  • Plastic build

Bottom line: The vacuum pick. Tightvac's patented lid pushes the air out as you close it, creating a near-vacuum airtight seal — and the opaque body blocks light. It's smell-proof, compact, and cheap, making it a favorite for fresh, discreet storage on the go.

Key details: Patented push-vacuum lid; opaque body blocks light; airtight + smell-proof; sizes 1–6 oz; pocketable.

Press the lid, and the air is gone. Tightvac's clever push-button lid vacuums out the air as you seal it, locking out oxygen (and smell) better than a simple screw-top. The opaque body blocks light too. It comes in sizes from 1 to 6 oz, it's pocketable, and it's inexpensive — a smart, portable airtight option.

Seal
Push-vacuum
Light
Blocked
Sizes
1–6 oz
Smell
Proof

Who should buy it: Buy this if you want a cheap, compact, smell-proof container with a vacuum-tight seal.

What we don't like: No built-in humidity control (add a pack), and plastic feels less premium than glass or metal.

11 · Best Pocket / Multi

Pop-Top Bottles (12-Pack, with Bags)

Pop-Top Bottles (12-Pack, with Bags)

4.4~$10–$18

Classic dispensary-style pop-top bottles in a multipack — cheap, airtight, and pocketable.

Pros

  • Dispensary-standard
  • Airtight pop lid
  • Pocketable multipack
  • Separate strains cheaply

Cons

  • Small each
  • No humidity control

Bottom line: The pocket multipack. Pop-top bottles are the dispensary-standard pocket container — squeeze and pop the lid, airtight when closed, and tiny enough for a pocket. A 12-pack (often with mylar bags) lets you separate strains for next to nothing.

Key details: Pop-top dram bottles; child-resistant pop lid; opaque options; 12-pack + mylar bags; the dispensary standard.

The little bottles dispensaries use. Pop-top vials seal airtight with a squeeze-to-open child-resistant lid and fit easily in a pocket. Buying a 12-pack (these come with mylar smell-proof bags too) lets you keep multiple strains separated and dosed out cheaply — ideal for organizing a stash or carrying small amounts.

Type
Pop-top
Lid
Child-resistant
Pack
12 + bags
Size
Dram

Who should buy it: Buy these if you want cheap, pocketable, airtight bottles to separate strains or carry small amounts.

What we don't like: Small capacity each, no humidity control, and translucent ones let in some light.

12 · Best Budget Smell-Proof

Blue Bus BUNKER Smell-Proof Stash Jar

Blue Bus BUNKER Smell-Proof Stash Jar

4.4~$14–$20

A compact, airtight, smell-proof jar that locks odor in for cheap.

Pros

  • Smell-proof + opaque
  • Airtight
  • Compact
  • Budget price

Cons

  • No humidity control
  • Small capacity

Bottom line: The budget smell-proof pick. The Blue Bus BUNKER is a simple, compact, airtight jar focused on locking odor in — opaque to block light, sealed to keep smell contained, at a friendly price. A solid no-fuss option for discreet storage.

Key details: Airtight smell-proof container; opaque light-blocking body; compact; budget price.

Smell-proof, simple, cheap. The BUNKER keeps things straightforward: an airtight, opaque container that contains odor and blocks light without any extras to fuss over. For a compact, discreet, budget smell-proof jar, it does the job well.

Seal
Airtight
Smell
Proof
Light
Blocked
Value
Budget

Who should buy it: Buy this if you want a simple, cheap, smell-proof and light-blocking jar.

What we don't like: No humidity control, and small capacity.

13 · Best Smell + Humidity

Smell-Proof Jar with Humidity Compartment (1/2 oz)

Smell-Proof Jar with Humidity Compartment (1/2 oz)

4.4~$15–$22

An airtight smell-proof jar with a separate compartment to hold a humidity pack.

Pros

  • Smell-proof + humidity slot
  • Airtight
  • Pack stays off flower
  • Affordable combo

Cons

  • Pack sold separately
  • Smaller size

Bottom line: The smell-plus-freshness pick. This smell-proof jar adds a dedicated compartment for a humidity pack — so you get odor control, an airtight seal, and humidity management in one container without the pack touching your flower. A clever combo for under $25.

Key details: Airtight smell-proof jar; dedicated humidity-pack compartment; opaque; ~1/2 oz; combines smell + freshness.

Smell-proof and humidity-controlled in one. Most cheap jars make you choose between locking in smell and controlling humidity — this one does both, with a separate slotted compartment that holds a humidity pack away from the flower while the airtight lid keeps odor in. A smart, affordable all-rounder.

Seal
Airtight smell-proof
Humidity
Dedicated slot
Size
~1/2 oz
Light
Opaque

Who should buy it: Buy this if you want smell-proofing and humidity control together in one affordable jar.

What we don't like: You supply the humidity pack, and the ~1/2 oz size is on the smaller side.

14 · Best Classic / Cheap

Ball Mason Glass Jar (Pint)

Ball Mason Glass Jar (Pint)

4.7~$8–$14 (multipack)

The classic airtight glass jar — cheap, reliable, and Boveda-ready.

Pros

  • Airtight + cheap
  • Reliable classic
  • Boveda-ready
  • Infinitely reusable

Cons

  • Clear glass (store dark)
  • Add humidity pack

Bottom line: The classic everyone has. A Ball mason jar is airtight, cheap, and reliable — and the moment you drop in a Boveda pack and keep it out of light, it's genuinely good storage. The no-frills classic that punches way above its price.

Key details: Ball glass mason jar; two-piece airtight metal lid; pint size; the cheap classic; pair with a humidity pack.

The original stash jar, and still a great one. A pint mason jar seals airtight with its two-piece lid and costs almost nothing in a multipack. Its only weakness is clear glass (light), which you solve by storing it in a cupboard — and adding a Boveda pack makes it humidity-controlled. Cheap, proven, and infinitely reusable.

The cheap perfect setup: a mason jar + a Boveda 62% pack, kept in a dark cupboard, gives you airtight, humidity-controlled, light-protected storage for a few dollars. It's the budget version of a CVault — just remember the dark cupboard, since the glass is clear.
Material
Glass
Lid
Airtight 2-piece
Size
Pint
Value
Cheapest

Who should buy it: Buy this if you want cheap, reliable airtight glass storage and don't mind keeping it out of light.

What we don't like: Clear glass lets in light (store it dark), and you add your own humidity pack.

How we chose

We grouped picks by what they do — humidity-control, UV-blocking, vacuum/pop, smell-proof — since that's how you should choose.

We prioritized a truly airtight seal (for freshness and smell) and light-blocking (metal or UV glass) above looks.

We covered every size from a pocket 1/8 oz to a curing-size canister, and add-ons like Boveda packs for any jar.

We mixed the trusted specialists (CVault, Boveda, Infinity Jars) with the best value and classic options.

Questions, answered

What is the best stash jar?

For most people the CVault is the best overall — an airtight, fully light-proof stainless container with a built-in holder for a Boveda humidity pack, so it protects flower from air, light, and bad humidity at once. For glass, Infinity Jars' UV glass blocks degrading light beautifully, and a Ball mason jar plus a Boveda pack kept in a dark cupboard is the cheap classic. Choose by what matters most: humidity control (CVault), light-blocking glass (Infinity), smell-proof and portable (Tightvac), or cheap and simple (mason).

How do you keep weed fresh in a jar?

Store it in an airtight, light-blocking jar with a two-way humidity pack, kept somewhere cool. The airtight seal blocks the oxygen that degrades and dries flower; an opaque or UV-glass body blocks the light that breaks down THC and terpenes; a Boveda 62% pack holds the ideal moisture so it doesn't dry out or get damp; and a cool spot slows everything down. That combination keeps flower fresh, potent, and flavorful for months. Avoid clear jars left in light and don't leave the jar mostly empty of air.

What humidity should weed be stored at?

About 58–62% relative humidity, with 62% the popular default. Below ~55% the flower dries out, becomes harsh and dusty, and sheds trichomes; above ~65% you risk mold. A two-way humidity pack like Boveda 62% holds that ideal window automatically by adding or removing moisture as needed — just drop one into any airtight jar. It's the single most effective upgrade for keeping stored flower in perfect condition, and it works in everything from a CVault to a mason jar.

Do stash jars block smell?

A truly airtight jar does — the seal that keeps oxygen out also keeps odor in. Metal containers like CVault and vacuum-seal containers like Tightvac are excellent at containing smell, as are quality airtight glass jars. A loose-fitting lid or a jar that isn't genuinely airtight will leak odor. For full discretion when you travel, pair the jar with a carbon-lined smell-proof bag, which adds another layer of odor control on top of the airtight seal.

Is UV glass better than a clear mason jar?

For light protection, yes. Clear glass is airtight but lets in light, which degrades cannabinoids and terpenes over weeks — so a mason jar is only good storage if you keep it in a dark cupboard. UV (black-violet) glass like Infinity Jars blocks that harmful light while still being a premium glass jar, so it protects your flower even sitting out. If you'll store in the dark, a cheap mason jar plus a humidity pack is great; if you want it out on a shelf, choose UV glass or opaque metal.

What size stash jar should I buy?

Match it to how much you store, and avoid a big jar left half-empty of air. A 1/8–1/4 oz pocket jar is for carrying a personal amount; a ~1 oz jar is the everyday sweet spot; and a 2 oz to 1-liter canister is for a larger supply or curing a home grow. A jar sized to the amount stores it better than a large one with lots of headspace. For keeping multiple strains separate, a multipack of small pop-top bottles works better than one big jar.

Can I just use a mason jar?

Yes — a Ball mason jar is airtight, cheap, and reliable, and with a couple of tweaks it's excellent storage. Drop in a Boveda 62% humidity pack for moisture control and keep the jar in a dark cupboard (since clear glass lets in degrading light), and you've got airtight, humidity-controlled, light-protected storage for a few dollars. It's essentially the budget version of a CVault. The only things a mason jar lacks are built-in light-blocking and a humidity-pack holder, both easily solved.