The 5 Inch Gray Poly Swivel Set of 6 by Service Caster features precision ball bearings for smooth and reliable performance. The bright zinc plated finish adds durability and corrosion resistance, while the polyurethane tread on polyolefin core wheels provide a cushioned ride and increased maneuverability. Perfect for material handling and caster applications, this set of 6 swivel casters offers a sturdy and efficient solution for a variety of industrial and commercial needs.