Shock-Absorbing Bolt-Hole Caster M16 Bolt Hole Dia M16 Mounting Bolt Dia Aluminum Caster Frame Material Powder Coated Frame Finish 300 to 999 lb Load Rating Range 330 lb Load Rating 1 Number of Wheels Precision Ball 9 1/16 in Mounting Height 6 in Wheel Dia 1 5/8 in Wheel Width Polyurethane Wheel/Tread Material 90 Shore A Wheel/Tread Hardness Firm Yes Non-Marking