【PREMIUM CRAFTSMANSHIP & MATERIAL】Gate helper wheels are made of solid tire-grade rubber material and sturdy steel with strong load-bearing capacity. Black powder-coated surface and hot-dip galvanizing process, wear resistance, corrosion resistance, rust protection for long-lasting outdoor use. 【SUPPORTS DOOR WEIGHT UP TO 500 LBS】Excellent quality 6\" gate wheel, can withstand weight up to 500 pounds, preventing gate sagging and saving gate hinges. This gate supporting wheel is designed 8-3/4\" from the bottom of the wheel to the center of the mounting tube gate frame. That means it can help lift your gate up to 8-3/4\"! 【ONLY for ROUND TUBES】The 6\" hard rubber gate support wheels with adjustable steel U-bolts for mounting, the wheel diameter is 6 inches, the total length is 10 inches, fits 1-5/8\" to 2\" round fence tubes. Please check your gate frame diameter before purchasing. 【EASY TO INSTALL】Install the gate wheel on the gate's lower tube and adjust to the desired gate height. Tighten the U-bolt with the included washer and nut securely with a wrench until the gate helper wheel does not slip on the tube.