Halifax or Vancouver our Low priced answert to the heavy weight objects movement, Wheel casters like our VXB005150PPB1 will be rolling your machine or equipment back and forth. Dia. Measured of the caster wheel in metric standard 150mm which is equal to 5.906" inch with imperial units. The thickness of the wheel is 45mm or 1.772" inch. The height of the wheel caster is 190mm = 7.480" inch. Mounted via a Top Plate that has a size of 115mm x 110mm x 6mm and the holes distance of 72mm x 85mm. Low drag was achieved by a Polypropylene core on a Polypropylene tire spinning freely with a Double ball beaing. Maximum load calpacity that could not be exceeded on each wheel, remember to add safety factor, when calculating the load capacity 1543 lb with a Side Brake type. The Temperature range is -40 to 180 F. FYI, you will need to buy the VXB005150PPB1 in order to get one :).