All new MPLS Helmet Lights now come with the ABR mount included. This item is only needed if you have an older lamp that did not come with it. The Above the Rail light mount (MPLS-ABR) is designed to free up valuable rail space, for use with communications devices, cameras, or other accessories. This mount is adaptable to several types of helmets, and compatible with Princeton Tec MPLS lights, including Point, Switch, Charge, Charge Pro and Switch Rail MPLS.