Spydercos TriAngle Sharpmaker is incredibly versatile. It includes two sets of high Alumina Ceramic 7 stones medium grit for aggressive sharpening and fine grit for professionalgrade finishing. Stones fit into keyed holes and a set of brass safety rods protect the users hand during sharpening. The triangular shape allows honing of serrated and plain edges. Slots molded into the polymer base have a 40 and 30degree angle for knives and a 12.5degree scissor setting. A groove running the length of the stone is for sharpening pointed objects like darts awls and fishhooks while a channel on the flipside allows for a benchstonetype set up. The TriAngle Sharpmaker includes instruction book and video."