PFERD bench sanding disc is made of regular aluminium oxide in a vitrified connection. These products are particularly suitable for high speed steel (HSS), steel, cast steel and cast iron. Application: deburring on semi-finished products and cast products. Regrinding and sharpening HSS tools such as drills and rotary tools. Various maintenance applications. Recommended Use If a bench grinding disc starts to show loading marks, use bandages on page 28. Suitable tool drives are bench and platform grinders. Safety recommendations: the maximum speed is calculated according to ANSI B7.1. Never exceed the maximum speed on wheel labels. Please note: smaller spindles often run at higher revolutions. Before assembly, all wheels must be visually checked for damage and cracks. Perform the ring test before assembly. An undamaged wheel gives a clear sound. Specification:8" diameter; 1" thick; 1.5" drill hole; 46 grit; 3600 RPM maximum rotation speed.