A mounting rail assembly comprises a rail configured to be coupled to a helmet. The rail may include a rear surface and a front surface with a mounting groove extending along a length of the front surface. The mounting groove may be open outwardly from a front surface of the rail and be configured to couple to a first accessory device at two or more positions along the length of the rail. A recess may be proximate an edge of the mounting rail assembly. The recess may be open generally perpendicular to the mounting groove and configured to receive a second accessory device. At least a portion of the recess may be positioned between the mounting groove and the rear surface of the rail.