By far the best quality on the market. The Registered Designed 32x30mm aluminium box section allows the rail to slide smoothly with the 25.4mm square. Available in white aluminium or anodised aluminium that won't blacken your hands or canvas. It has a strong yellow zinc hook and Hi-Tensile yellow zinc steel spigot with our Easy Grip Wheel for adjustment. The rail is also supplied with our Nylon-R roof rail bracket.