what all the best bongs are made of. When a bong or any glass pipe is made with borosilicate it is typically top of the line quality and you know it isn't some china sweat shop bullshit. True pot heads only own boro, and drop thousands of dollars on it a year collecting different artist.
Novice Pothead: Yo dude you wanna buy this bong its like $60.

Season Stoner: hahaha hell nah dude are you kidding me that shit is probably not even borosilicate and some made in china bullshit. Im gonna go buy a Hitman, Soverignty, Stone, or some artistic shit.

Novice Pothead: whats boro?

Season Stoner: the fucking glass your holding in your hands.
by RipBongWinkle December 2, 2011
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