Diving Flashlight diving underwater 100m,it has strong waterproof an effective solution to keep sealed under water pressure by operating with the principle of magnetic sensors adjust brightness with the Rapid Response Activation ring Use Cree MC-E K-bin LED LED life span: 50,000 hours four modes: 100% brightness, 50% brightness, 20% brightness, flashing (30HZ) constant current circuit, constant luminance 2 x 18650 Li-ion batteries Size:215mm (L) x 55mm (D) Output :660 Lumens Material: T6 aircraft Alluminium alloy Finishing: 3 grade hard Anodic oxidation Use optical lens with toughness and transparency. Excellent scratch resistance. Water proof: IPX-8