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Title: useful as vacuum chambers
Review: I got this 3-pack with my FoodSaver kit and while I haven't used them for storage, they're handy for sealing mason jars without the adapter cap thing, up to wide mouth quarts in the big one. Just put the jar with disk on top and seal away-- the pressure should make the mason jar lid flutter a little as air escapes. Release the pressure in the canister and see if you can lift the jar out by the lid. It might take two tries, but it's very handy; for the price of this 3-pack, you could get two dozen mason jars.
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