Made from alloy, and supplied with a plastic cover, the RR1500 is ideal for use when needing to get ladders on and off your roof racks, with out the cost of a full ladder system. Supplied with a pair of roller bushes and brackets to attach to a Rhino Heavy Duty bar. It is designed to suit a cross bar measuring 1500mm. NOTE: The roller is actually cut 70mm shorter than the labelled length to allow for the mounting bracket to fit onto the appropriate bar size.