【Important Note】: The base of this grinding wheel is made of tough black plastic, not compatible with grinders that use a brass-colored metal rod base. Here's info about the replacement grinding wheel for the Dog nail grinder: Material: The grinding wheel is made from alloy sand. Generally, one grinding wheel can last a long time, depending on how often you use it. Cleaning Method: After grinding pet nails, you can easily clean the wheel with an eraser. Replacement Procedure: Changing the grinding wheel is simple; just take out the old one from the slot and put in the new wheel. Suitability: Perfect for delicate tasks and finer work.