Use Cookie Paddles ONLY with a metal driver. Cookie paddles work well for all but the stiffest cookie dough. Use the Bosch Dough Hook when using stiff ingredients (raisins, nuts, oatmeal, etc.) or making extra large batches. The metal driver is hand wash only. It will discolor with dishwasher use. DO NOT USE a plastic whip driver with the cookie paddles. Plastic whip drivers are only designed for use with wire whip attachments.