This rigid plate caster has a 1 1/2 x 5-inch wheel with a silver core. With a load rating of 500 pounds, each caster features a steel frame with a zinc finish. The mounting plate measures 4 1/8 x 3 3/8 inches, with a 5/16-inch mounting bolt diameter and an inside/outside bolt hole spacing of 2 3/8 x 3 1/8 inches. Use item number WRT515B for replacement wheels.