This listing is for a steel small wheel holder for 2x72" belt grinders & a set of 5 small wheels. We make the holder out of steel instead of aluminum because the hard outer shells of the bearings eventually wear aluminum out when the small wheels are continually removed & inserted; our bearing pockets are also case hardened. It attaches to a tooling arm (available separately from our Ebay store) with a 1/2-13 bolt & a 3/8-16 bolt (supplied). Finish is durable powder coating. For the small wheels we use 1018 steel & the wheels are surprisingly durable & grind finger grooves precisely. The set consists of 5 popular diameters: 1/2", 5/8", 3/4", 7/8" & 1". As with all small wheels it is important not to spin these too fast, the bearings are too small to handle high rpm's. We find that a 1800 rpm motor with 4" drive wheel provides a speed which is tolerable for moderate lengths of operating time. Keep checking the bearings for heat even at this speed. Another excellent option for turning these wheels slowly is our 2-Speed Lightning wheel which has a 4:1 reduction so it turns at 1/4 motor speed.