Adam's Gen2 Absorber Backing Plate (PN: GEN2-04) The Adam's 3/4" soft backing plate absorbs uneven surfaces and reduces vibration. Fits right into most polishing machines including our suggested Porter Cable 7424. The Adam's Super-absorber, always-centered backing plate works with Adam's: 7 1/2 Inch Orange Swirl Killer Pad 7 1/2 Inch White Fine Polishing Pad 7 1/2 Inch Black Ultra-Fine Polishing and Waxing Pad