4pcs Heavy Duty PU Swivel Castor Wheels Trolley Furniture Caster Rubber Specification: Type:Swivel Castor Wheels Color:Black Material:Steel、Plastic Load Rating:App 200KG(50KG each) Overall Height: App 9.5cm/3.7" (without screw) Wheel Size: Diameter.: App 5cm / 2" Wheel Width: 2.5cm Wheel Type :Twin ball roller bearings、 non-marking polyurethane material Features: Easy to install. Double ball bearings swivel head. Ideal for a huge variety of uses from DIY to industrial applications (home、 schools、 shops & hospitals) Package included: 2 x Swivel with Brake Wheels 2 x Swivel Wheels