The quick Release light holder by M-Wave features a super lightweight body (19 grams) composed of CNC-machined aluminum. It is 47 mm (1.85 in) in length, and mounts at qr with a 5 mm Hex wrench. Comes packaged on a header card. M-Wave is our most popular line of products with the widest variety of cycling and sporting gear. From locks to lights, bags to bar ends, M-Wave has you covered. Good price, great quality.