Designed to move very heavy loads on inverted angle iron tracks without destroying floor surfaces. Can also be used to roll on regular floors. When operated on tracks, they offer a most effective low-cost method of taking loads off the plant floor and establishing production line flow. V-Groove wheels, in either semi-steel or ductile iron, come with standard hardened alloy steel roller bearings. Machined groove and tread 7/8" wide x 7/16" deep. FOB Shipping Point.