The OEM Prismacolor Design Kneaded Rubber Eraser SAN70531 is designed to both highlight and cleanly erase chalks, charcoal, pastels, and colored pencils. This premium rubber eraser molds easily into the size and space of what you're erasing. To maintain its effectiveness, clean the eraser by gently kneading it in your hand. The large eraser size measures 1-3/4" x 1-1/4".