Swivel castors with heavy pressed steel castor bracket,,fitted with a special tyre design Injection polyurethane on nylon core fitted with 2 precision ball bearings. These swivel casters range from 150mm - 200mm and have a capacity up to 400 Kg per caster. Our OPU design centre core was constructed out of necessity to help overcome a issue which most nylon centred wheels experienced when subjected to challenging environments ie abusive or misuse. Polyurethane on nylon centres are quiet ,provide soft cushioned ride and are unlikely to damage floors. Typical applications for our OPU are food and pharmaceutical where duty and aesthetics are a consideration . Ball bearing Injection polyurethane was once considered expensive which deterred many from using. Our aim has to always offer value for money our polyurethane is now become much more popular and the cost have come down. We recommend all food companies to use this very versatile castor you want be disappointed. Our Injection polyurethane makes the tyres soft to the touch and as such provides a very smooth and cushioned ride and will help reduce any likely vibration.