PRI's flip up rear sight is constructed of T6 6061 hard coated FDE anodized aluminum.  This sight is designed to work on a same plane aperture system that allows the operator to choose between 2 different setting without loosing zero.  The low profile sight will allow the use of optics and top rails.  The sight lifts and locks in the up position and to lower you need to push the detent button.  The sight also has a side windage adjustment.  From the base to the peep is 1.4" and weighs 2.4 ounces.