Allpoints 26-3378 4" Swivel Stem Caster with Brake for 1" O.D. Tubing - 240 lb. Capacity

expansion stem swivel caster w/ brake expands to 1" exact stem size 0.983" od wheel size 4" ball bearing dark grey hub, grey polyurethane tread max load per wheel lbs. 240 tread width 1 1/4".