Stink bomb
A stink bomb is a packet that, when pressed, releases bad odors. A common ingredient in stink bombs is ammonium sulfide. They are used for practical jokes on other people. Some use it to imitate farting, and some use them to embarrass other people, by placing them in the seat of their pants. When the targeted person sits, the stink bomb releases bad odors, similar to menthol. Stink bombs do expire, since the longer they are not used the less effective they are. Stink bombs do have guides. Stink bombs are also lightly regulated, since some can have toxic waste inside. it is similar to an instant cold pack.