Housing made of pressed steel, zinc plating, single ball race, swivel head. Wheel material: polyurethane tyre PU with cast iron core, steel roller bearing. Diameter x tread width: 125x50mm. Available in 100x50mm, 125x50mm, 150x50mm, 200x50mm. Load capacity: 240kgs to 500kgs Complies with international quality standard ISO 9001-2000.ROHS NSF. Export standard carton 54x21x16 10pcs/ctn 24kgs/ctn