Castor in polyamide and mineral fiber, wheel with TPU thermoplastic polyurethane and polyamide 6 centre, steel plate with high thickness and polyamide threadguards. Mineral fiber material gives a great resistance. While polyurethane tread projects against oil and acid. Recommended for armchairs, chairs and forniture items where it is necessary to combine aesthetics with guarantee of not damaging the most delicate flooring.