Features:OOTDTY brand new and excessive qualityMaterial: Made of nice metallic + nylon, solid and durable.There are four styles for you to choose from, choose the corresponding specifications in line with your needs.Carrying capacity: sturdy and load-bearing.Features:Thicker metallic iron for shell, hardness and for stronger load-bearing capacity.Application: used for tune reversal, rolling gate, sliding door, industrial machinery, cord rope instruction manual device, container rack, youngster door, canine door,Specifications:Material: MetalWeight: 42g/32gSize: 41mm/1.61inchType: Double Convex Wheel/Double Wheel/Single Convex Wheel/Single Wheel(optional)Package Includes:1x Sliding Door RollerNote:1.Please enable 1-2cm errors due to handbook measurement, just be sure you do not intellect before you order.2.Due to the difference between assorted monitors, the picture might not mirror the actual coloration of the item.