Optimized for use with the MILWAUKEE M18 FUEL 21mm Random Orbital Polishers. Our 6 orbital polishing pads are compatible with all 6 hook & loop backing plates. Foam design reduces friction which increases durability and reduces foam fatigue. The center cooling chamber dissipates heat away from the center of the pad, reducing temperatures and increasing durability. The tapered edge prevents pad rolling and provides great pad rotation which allows them to be used on curved and contoured panels. Provides users with all-day comfort and more control.