Improved version: Adjustable and wall-mounted floor guide. It provides stability and smoothness for sliding doors. The smooth roller will not make your door feel uncomfortable. Beautiful and practical. It is perfect for both expert and non-expert users due to its easy installation. Material: The sliding door wheel is made of solid steel and nylon external parts, which provides premium quality to the product. The external bearings provide a smooth surface that is able to reduce the friction caused by sliding iron doors; in addition, they are durable and impact-resistant. Humanization: 1. Hot-dip galvanized, 2. Zinc layer thickness: 120g 3. Salt spray test time: 72 hours (no rust) 4. Error: 50mm. Application: Electric door inner wheel/sliding door nylon sleeve wheel/iron door inner wheel/electric door guide wheel/track wheel/pulley. Easy to install: The sliding barn door kit is able to keep the door perfectly balanced on the bearing guide, prevent swinging as a sliding door guide, so that the sliding barn door hardware will not make noise and remain balanced. Suitable for sliding garage doors, interior doors and gates etc. Uses: Nylon Wheels as Sliding Door Guides (2pcs*40mmx60mm), for Sliding Doors, Electric Doors, Sliding Rollers, Garage, Sliding Doors, Sliding Gate Wheels, Conveyor Roller or Conveyor Roller, Pallet/Pallet Wheels, Worn Roller Spare Parts | Applications: Industrial and General Purpose.