3" Metal Ball Caster with Rubber Tread, Windsor Antique, with 3/8" x 3/4" Threaded Stem Capacity: 100 lbs Diameter: 3" Mounting: Threaded Stem -3/8" diameter x 3/4" long Finish: Windsor Antique with Rubber Tread Bearing: Self Lubricating Acetyl Resin Bearing