Electric stapler fastens up to 20 sheets at a time with a smooth, motor-driven mechanism. Battery power is fueled by four AA batteries (sold separately). Stapler includes a low-battery light so you know when to change batteries. Clear-view window allows you to see where the staple will go. Design also includes push-button staple-loading for simplicity, a 105-staple capacity and 5/16" throat depth. Electric stapler uses S.F. 3 premium staples.