MATERIALS: The rolling gate wheel is made of high quality PU anti-corrosion steel, sturdy and durable, it has the characteristics of anti-oil, anti-corrosion and anti-rustDIMENSION: The total mounting height is 25.5cm; wheel diameter is 5cm; the mounting plate is 7.54.5cm (LW)LOAD CAPACITY: The maximum load capacity of each caster is 50 kgTOP DESIGN SPRING: The gate"s retractable wheel allows for 6cm of vertical movement, automatically adjusting the height on uneven ground to prevent it from sagging, while ensuring the gate stays in contact with the ground when you swing it open and close easily and smoothlyEASY TO INSTALL: Comes with 4 bolts, sturdy universal mounting plate with 4 holes to fit wooden garden gate, driveway gate and at the yard fencePlease carefully confirm your size, name &number and shipping address before placing the order, thus to assure the delivery efficiency and avoid unnecessary troubleAbout Shipping: All items will be shipped within 3 business days after the payment is received. Most times you will receive them within 6-8 days then. The specific delivery time is depend on circumstances.Any questions, please feel free to contact usDuring the shopping process, if you have any questions, please feel free to consult us, we will reply you within 12503 hours, wish you a happy shoppingThanks for your cooperation and we& 39;ll make you feel satisfied."