Check the listing for details. Skelang 2 Spring Loaded Gate Caster Retractable 2-1/2 Swivel Gate Caster W.... Condition: New. Listed at 25.06 USD. Spring loaded gate caster is made of thick steel and very strong construction, PU material wheel is very durable, swiveling great and rolling smoothTotal height is 11", wheel diameter is 2", mounting holes distance is 2.95" length by 1.77" width, retractable length is 2.55"Max load capacity up to 125lbsDesigned to allow gates to open and close freely by spring-loaded system adjusting height on uneven ground, avoiding the sagging gate. As a shock absorber made wheel rolling smoothly to save energy when you push gateCome with 4 bolts, it’s easy to install on your gate; fit to wood or metal gates and fences Spring loaded gate caster is a good solution when your gate rolling on the uneven, which allow gates to open and close freely by spring-loaded system adjusting height on uneven ground, and avoiding the sag of the gate. as a shock absorber make wheel rolling smoothly to save energy when you push gate Specifications: Wheel Diameter: 2" Mounting Height:11" Retractable Height: 2.55" Material: Steel Package Includes: 1 x Spring Loaded Gate Caster 4 x Bolts