it doesn't even have to be a mason jar... ANY glass jar that comes with a lid will work just fine.... jelly jar, pickle jar, whatever.... i have a little glass olive jar for my better shit and you can't smell it unless you open it... and then wow lol.... if you're still worried about it that much, i mean if you wanna get really paranoid with it, put it in a glass jar, put that glass jar in a ziplock bag with a dryer sheet in it... even if somehow a little bit of the smell does get out of the jar (highly unlikely) there's no way it'll overpower the dryer sheet.