100mm Machine Cast Nylon Wheel fitted into an extra robust Fabricated Prime Plate Swivel Castor that has a double thrust bearing from the swivel head to optimise the load potential. The fixing bolt spacings are the ecu Standard size of 80x60mm. The load capacity of the castor is 900kg at http://wheels-and-castors02211.newsbloger.com/16922641/heavy-duty-castors-can-be-fun-for-anyone