• Patented, see-through design allows interrupted cut which reduces heat up to 30% over standard discs
• The scooped holes create air flow to pull swarf away from grinding zone, cool cutting and extended product life
• 5 deg back-up pad for full utilization of discs - no gouging
• Quick, tool-free, twist-on and off Speed-lok fasteners
• AVOS triangular speed-lok back-up pad
• Hard density
• Quick change face mounting
• Arbor hole back mounting type

Norton® 63642502985 Backing Pad, Diameter: 4-1/2 Inch, Max. RPM: 13000, Thread Size: 5/8-11 UNC, Plastic, Black