A credit card type dental floss dispenser for carrying in a wallet or the like. The urging unit moves the tool with respect to the workpiece. A logic state of the resistive device is determined based on a logic state of the external output voltage. 5 gcm3, and a Rockwell Hardness ranging from 50 to 92. The lens barrel has an outer thread threadedly engaging with the inner thread of the rotor, and an internal thread formed on an inner surface thereof.