Instapark&reg; 2.50" B Premium Quality Tobacco Herb Grinder. Made of durable aircraft-grade aluminum alloy, 2.5 in diameter. Anodize surface provides enhanced hardness & smooth, scratch-free finish Diamond shaped & CNC (Computer Numerical Control) tooled teeth for easy, efficient & effortless grinding 4-chamber design including magnetic top, bottom, stainless steel micro sieve & pollen catcher Stylish design with compact size and light weight for easy storage