Testicules is the communal drinking vessel on long camping trips, usually used to store other forms of food prior to use as a fluid reservoir and is usually in the shape of an animal. Primary liquids dispensed by Testicules are Tang and Kool-Aid.
The most common container to be converted to Testicules is the Army-Sized Animal Cracker plastic bear. Also, the only way to have a true Testicules is to consume the crackers from the bear before filling with liquid, none can be thrown away.
The origin of Testicules is unknown, but is rumored to have started as a sort of rite of passage among young teens.