The Staedtler/Mars cordless rechargeable erasing machine can be used for cleaning small delicate areas and for larger jobs too. It runs either on its NiCad battery or direct 120 volt power. The lightweight plastic housing runs cool and fits comfortably in the hand for either right or left handed operation. Comes complete with recharging stand, and a 7 foot cord. This eraser uses an eraser rod that is 5-1/8" long with a 0.275" dia. The eraser rod is made of the same white vinyl material as the blocks.