The Models 525/528 are vacuum assist orbital sanders with a 3/32" offset. The smaller rectangular orbit allows better sanding access for bumpers, recessed areas, and new panel prep. Both sanders use standard 2 3/4" velcro sandpaper rolls. Velcro pads securely hold scuff pads for easy new-panel prep. Built-in pad release feature. Models 525 2 ¾" x 5 ½" VA Velcro Pad Models 528 2 ¾" x 5" VA Velcro Pad.