SLX Ver. 1 Ceramic Coated Non Stick GrinderThe proprietary ceramic coating on all surfaces inside and out means no more sticking, no more grinding to a halt 100% non toxic, FDA approved ceramic coating ZERO Teflon or PTFE Large 4 Piece is 2. 4" (62 mm) in diameter 57 trapezoid shaped teeth each feature four cutting edges to evenly shred your material into an airy, multi use grind that falls freely through thoughtfully designed drop through holes into the chamber below Popular 4 piece design is