3M Constructed of a soft durable foam. When used with a clean sanding Hookit backup pad it increases conformability allowing the technician to follow contours and get in closer to most edges while maximizing dust extraction. Attachment type: Hookit. Black color. Converted form: backup pads, disc. Density rating: soft. Diameter: 5-inches. Equipment – machines: random orbital sanders, rotary sanders. Form type: fabricated – clean sanding. Front color: black. Hook type: 2. Max OPM: 12000. Maximum RPM: 12000. Number of holes: 44. Thickness: 0.50 inch.