Feature: 1. Spring loaded designs make gates to open and close freely by automatically adjusting height on uneven ground while eliminating gate sag 2. The product is a heavy duty caster, the wheel has a maximum load capacity of 90kg 3. This spring caster can also withstand exposure to chemicals and solvents, very durable 4. Made of premium rubber material and high quality metal construction, sturdy and durable 5. Heavy duty universal mounting plate with 2 holes to easily attach to wooden gates or along horizontal or vertical rails of a tubular farm gate, easy to install Specification: Item Type: Gate WheelMaterial: Aluminum, rubber Purpose: Multifunctional casters, shock absorption Load Bearing: 90 kg / 198.4 lb(approx.)Caster Size: Approx. 12.7cm / 5in Size: Approx. 310mm / 12.2in 130mm / 5.1in 125mm / 4.9in 220mm / 8.7in 250mm / 9.8in 280mm / 11in M8 x approx. 95mm / 3.7in Thread Length: Approx. 52mm / 2in. Package List: 1 x Caster1 x Damping Device3 x Screw3 x Nut3 x Gasket