•Sizes available: 25mm, 38mm, 55mm
•check pictures for complete measurement
•Advantages
•1.High speed bearing push and pull easily durable service
•2.High quality Nylon roller with good wear resistance to keep the quiet and smooth running
•3.Pure nylon material: inclusion-free, high strength, seamless ,ultra-smooth,noiselessly
•4.Manufacturer own mold: direct marketing, superior quality, price advantage
•Installation
•1.According to the length,width,height and weight of door,to choose the matching pullers and running track
•2.Make sure maximize security and stability of pulley,avoid screw loosely
•3.Keep upper running track and bottom guide channel vertical,make door ultra-smooth
•allow 1-2cm error