iPoint Ball Battery Pencil Sharpener features a proprietary two-blade technology to sharpen a standard-size pencil twice as fast as comparable sharpeners. Sharp Sense technology allows you to feel when the pencil is at the optimal point. Blades are made of hardened carbon steel for strength and precision cuts. The outer shell is made of sturdy plastic for durability. Safety cutoff shuts off the pencil sharpener when the see-through shavings reservoir is removed. Ball-shaped pencil sharpener operates using four AA batteries (sold separately).