Wheel casters like the 4inch-Lock-Swivel-Caster-031 are used to roll your built machine or equipment back and forth. Diameter of the caster wheel is a metric standard 100mm that is equal to 3.937" inch with imperial units. The wheel has a width of 26mm=1.024" inch. The caster dimensions heightwise is 134mm/5.276" inch. Mounted via a Top Plate that has the size of 75mm x 75mm and the holes distance of 55mm x 55mm. Rolling with a wheel core material of Grey rubber and a Grey rubber tire rolled over Plain bearing. Bearing in mind that every caster wheel has the load capacity of 99 lb with a Swivel and Upper Locking type. Last and not least the temperature range = -40 to 180 F. Enjoy our 4inch-Lock-Swivel-Caster-031, we wish all the best in your project.