Human Grade Grinder 8ATThe Human Grade 2. 5" (63mm) 4 Piece Grinder combines a notched, curved body design for superior grip with a built in ashtray for added convenience. This multi functional 4 piece grinder ensures a smooth, consistent grind while keeping your setup clean and efficient. Retail Unit: One (1) Grinder Pieces: 4 (Four) An upper chamber, grinding chamber, pollen screen, and a bottom chamber for collecting the finer particles Size: 2. 5" (63mm) It's the