C4 LED delivers 15,000 candela peak beam intensity; 150 Lumens. Solid state power regulation provides maximum light output throughout battery life. Runs 3 hours. Tailcap push button provides one handed momentary or constant "on" operation. High impact super tough nylon polymer for exceptional durability and a sure grip. IPX7 rated design; waterproof to 1 meter for 30 minutes. Powered by two 3V CR123A lithium batteries (included).