Bolt Hole castors with a Pressed Steel castor bracket, fitted with a Rubber On Cast Iron Core wheel. These Bolt Hole casters range from 150mm-200mm and have a capacity up to 350 Kg per caster. Elasticated rubber on cast iron tread castor wheels have higher capacity than standard rubber and are very strong. These castors do not mark floors or develop flats. The load carrying capability of this rubber castor is allot higher than normal rubber castors. Softer tread castor tyres are useful for towing equipment and offer good all round performance. They are quite running.