The RUPES 50mm (2 inches) iBrid Backing Plate is a replacement backing plate for use with your iBrid Long Neck or iBrid Short Neck polisher. This plate is identical to the backing plate provided in the original iBrid kit. Use the RUPES 50mm (2 inches) iBrid Backing Plate with RUPES 70 mm (2.75 inch) Foam Pads.