This inner flange backing pad fits for Milwaukee 2680-20, 2680-22, 6116-30, 6116-31, 6122-30, 6122-31, 6123-30, 6123-31, 6140-30, 6140-33, 6148-31, 6160-30, 6160-31, 6161-30, and 6161-31 angle grinders. It has 5/8-11 arbor hole to fit most grinders and is made of aluminum alloy. This replacement part is easy to install and provides better durability for your grinder.