Thisderwent battery operated eraseris a very handy tool for all artists it erases quickly and offers you accurate and precise control complete with on and off control button which is positioned so it is held like a pen this handy battery operated eraser is perfect for left and right handed use also included in the pack are eight long replacement erasers enabling you to refill your eraser device whenever you need tothis handy tool requires two aaa batteries not included size 203 x 79