roller door parts 1.Material:Nylon&steel for the roller 2. shaft 11mm on roller 3.Used as garage door ... door and industrial door hardware..Material: Steel and Nylon for the roller.Nylon,2" , shaft 11 mm, L=118 mmNylon,2 ... punching machines, welding machine, polish machines...Processed materialstainless steel, copper, carbon steel (according to customer's requirement)Surface treatmentHot galvanized, ...