Swivel castors with heavy pressed steel castor bracket, fitted with an Injection polyurethane on nylon core fitted with 2 precision ball bearings. These swivel casters range from 100mm-200mm and have a capacity up to 500 Kg per caster. Injection polyurethane on nylon core wheel are very popular for many reasons they are smooth, provide quiet running with great floor protection. Why not add ball bearings centres as an option to reduce rolling resistance improving mobility. Polyurethane is a Non-Marking wheel material that offers incredible load capacity compared to many other tyres materials. They are light in weight and very hard wearing and priced competitively. They have become our wheel of choice especially when used with ball bearing centres. They provide a cushioned ride which helps the user experience and greatly reduces bracket stresses and wear helping castor life improves user experience.