[SPRING-LOADED DESIGN]: This gate roller adopts advanced spring-loaded design, which can automatically adjust the height on uneven ground, prevent the door from sagging, and can open and close the door freely. you to maintain contact with the ground when opening and closing the door easily, thus reducing noise! [HEAVY DUTY CASTERS]: The gate spring caster is made of high quality PU material and electroplated alloy, strong and durable. The swivel wheel has a maximum load capacity of 60 kg and can withstand exposure to chemicals and solvents. These are the ideal gate wheels for wooden and mental gates. [GOOD SHOCK ABSORPTION]: The design of the PU wheel and the spring-loaded clamp promote smooth operation of the caster when rolling on uneven or rough surfaces, reducing friction with the ground, making it easier to move and opening or closing the gate easily, with shock absorption effect. [EASY INSTALLATION]: Heavy duty universal mounting plate with 4 holes for easy attachment to wooden doors or along horizontal or vertical guides of a tubular door, fits perfectly and works well. This is the portal wheel robust perfect for your daily life. [WIDE APPLICATION]: This heavy duty gate wheel can be applied to wooden garden gates, front gates and yard fences, revolving gates, sliding gates, storage racks, carts , flight cases, carts, tool boxes, speakers, cabinets, amplifiers, equipment racks, various furniture, etc., it can bring great convenience to your life.