Listing is for 1 (One) Service Caster 6" x 3" Polyurethane on Cast Iron Keyed Drive Wheel.
Bore Diameter: 1-1/2"
Hub Length: 3-1/4"
Tread Durometer: 90-95 Shore (A)
Wheel comes standard with 2 set screws. One on the keyway and one 90 degrees from it.