I have about 7 jars that I got from my old science teacher. They are meant to store chemicals, mixtures, and all that other good shit so absolutely no smell gets out. They were brand new so no chemicals in them. They range from about 2" round x 4" tall to about 1/4" round x 1" tall. Perfect little things. As long as theres no smell on the outside(wash it off REALLY good) I can get past drug dogs like nothing. I use gloves when im gonna have to get past dogs though.