Description: MATERIAL: The v-groove are made of quality galvanized steel, sturdy, sturdy, erosion resistance and waterproofSIZE: Wheel diameter 1.2 inches, interior diameter of the wheel 1.26 inches. Fit to 90-degree V-shape track(Please confirm your size of V Tracks before order)LOAD CAPACITY: Bracket thickness total loaded is 460lbs capacity per caster, easy to carry up heavy duty gateROLL BEARING: Double roll bearings slide stably and smoothly, make it easy to push the gateMUTI-APPLICATIONS: Fit to heavy duty sliding gate, factory door, industrial machines track project, dog gate, garage door, garden gate. Specification: Material: Metal Package Includes: 4pcs Sliding Door Wheels Note: Please allow slightly errors due to manual measurement and different monitors.