Quiet operation for less classroom disruption. Heavy duty motor engineered for high volume use. Auto reset motor shut off prevents overheating for safer operation. Extra durable outer case. Automatic Pencil Stop prevents oversharpening. Multiple size dial sharpens wood, composite, and recycled pencils regular or children's thick size. Extra large, see through receptacle for easier, less frequent emptying. Safe start will not operate if receptacle is not closed. Non skid feet for A+ safety. Two year warranty.