Eraser Wheel has serrations for improved cooling effect air flow.
Dynabrade surface grinding wheel has a diameter of 4 in. The quick change attachment allows for easy mounting to the tool or pad. In addition to the other aspects of these parts, another important component of these is the thickness. This Dynabrade part is 1 1/4 in thick. All abrasive products that rotate or spin, such as the ones in this category, have a maximum speed at which you can run them. This Dynabrade surface grinding wheel can be run at a maximum speed of 4000 RPMs.

3M 77197, Scotch-Brite™ Roloc™ Deburr and Finish PRO Unitized Wheel,TR, 3 in x 1/8 in x NH, 8C CRS+, 7100109130, 40/box
Dynabrade 31920 - 1-1/4" (32 mm) Static Conductive Hose, Black
3M 11411, Roloc Disc 361F, 50 YF-weight, TR, 1 in, Die R100N, 7000045095
3M 36877, Self-Stick Liquid Protection Fabric, Blue, 6 in x 300 ft per Roll, 7100169347, 4 Rolls Per Pack
3M™ 17379, Versaflo™ Length Adjusting Breathing Tube BT-30, 7100009685, 1 EA/Case
3M 01328, PSA Cloth Disc 348D, P180 X-weight, 3 in x NH, Die 300V, 7000045068
ACS Diamond Cloth Belt, CX1250 3/8" X 120" 125U
Dynabrade 53270 7" (180 mm) Dia. Right-Angle Disc Sander 
