2-1/4" Metal Ball Caster with Rubber Tread, Bright Brass, with 7/16" x 1-7/16" Grip Ring Stem Capacity: 75 lbs Diameter: 2-1/4" Mounting: Grip Ring Stem - 7/16" diameter x 1-7/16" long Finish: Bright Brass with Rubber Wheel Tread Bearing: Self Lubricating Acetyl Resin Bearing