Chef&rsquo;sChoice 312 Diamond UltraHone Electric Knife Sharpener for Straight and Serrated Knives Diamond Abrasives Precision Angle Control Made in USA, 2-Stage, White (Discontinued by Manufacturer) Sharpens both straight edge and serrated knives to better than factory sharpness Two stage sharpener with precision angle control 100% diamond abrasives in stage 1 and 2 Advanced micron size 100% diamonds in Stage 2 Fast, foolproof results