Listing is for 1 (One) Service Caster 6" x 1-1/2" (6" x 2" pictured) Polyurethane on Cast Iron Keyed Drive Wheel.
Bore Diameter: 20mm
Hub Length: 1-5/8"
Tread Durometer: 90-95 Shore (A)
Wheel comes standard with 2 set screws. One on the keyway and one 90 degrees from it.