Rupes LHR 21ES 6" Backing Plate is a replacement backing plate for LHR21ES, LHR21II and LHR21III Big Foot Random Orbital Polishers. High quality backing plate, that in combination with BigFoot polishing foams, creates a system that significantly reduces vibration. The holes in the backing plate create an air flow that dissipates heat and keeps the work surface at an acceptable temperature. The material used in the fastening system creates an effective anchoring system, giving the foam exceptional stability while the tool is in use.