Fits most firefighting helmets, both traditional and modern styles. The Blackjack helmet flashlight holder accommodates 4-AA size lights from Pelican, Streamlight, Kohler-Brightstar, and Underwater Kinetics. The Blackjack will also accommodate the new generation of 123 size lithium powered lights from Surefire and Pelican. Superior under brim patented design securely holds the light on the helmet where you put it, where you need it. Built from aircraft grade 6061 aluminum, not stamped stainless steel, or thermoplastic, so it can stand up to the same punishment that you do.• Weight: 1.8 oz