This swivel plate caster is made for medium-duty applications and features a 1 1/2 x 6-inch phenolic wheel with a black core. This caster has a zinc frame and load rating of 750 pounds. The mounting plate measures 5 1/2 x 4 5/16 inches, with a 5/16-inch mounting bolt diameter, an inside bolt hole spacing of 4 1/8 x 3 1/8 inches, and an outside bolt hole spacing of 3 1/8 x 4 1/8 inches. Use item number 5-6-339 for replacement wheels.