Iron-core pu caster6*2 inch 1,swivel top plate ,pu&iron wheel 2,plate Zinc or spray plastics 3,steel thickness 5 ... .5mm or 6mm Iron core pu caster 6*2 inch ... 1,swivel top plate ,pu&iron wheel2,plate Zinc or spray plastics3,steel thickness ... x 50, 200 x 50,250*50,300*50mm 6 inch Iron-core pu caster