Bolt-Hole Caster, 7/16 in Bolt Hole Dia., 25/64 in Mounting Bolt Dia., Steel Caster Frame Material, Zinc Plated Frame Finish, 0 to 299 lb Load Rating Range, 150 lb Load Rating, 1 Number of Wheels, Ball, 2 in Mounting Height, 1 3/8 in Wheel Dia., 1 1/8 in Wheel Width, Polyurethane Wheel/Tread Material, 90 Shore A Wheel/Tread Hardness, Firm, Yes Non-Marking Bolt hole casters, also known as hollow kingpin casters and stemless casters attach easily to objects using a mounting bolt with the specific length and thread that fits your application. They can also be directly mounted to wood using lag bolts.