Whether you have a new creeper or it’s ten years old, you'll really feel the difference! They make a vast improvement in operation over standard, hard plastic caster wheels. Made of superior formulation HYPER-FLEX polyurethane and uses high precision bearings. Experience little or no rolling resistance! The unique polyurethane material and design allows smooth, unimpeded rolling for indoor/outdoor ease of movement–over cracks, washers, misc. debris, etc. Fits Most Standard Caster Assemblies. • Available in red or black with Cool Side Graphics. Rides on precision ABEC high quality bearings. • Installs in a few minutes with two 5/32 hex wrenches (not included). • All hardware is included.