Bolt hole bracket with black rubber with steel core rim wheel. Housing made of pressed steel, zinc plating, double ball race,swivel head.Wheel material: Rubber tyre with steel core, plastic roller bearing.Diameter X tread width: 80X29mm.Available in 100X29mm, 125X34mm, 160X40mm,200X50mm.Load capacity: 50kgs to 180kgsComplies with international quality standard ISO 9001-2000