Streamlight SURVIVOR C4 LED Flashlights is two to three times brighter than previous LEDs, plus provides 50,000 hours of life. Two brightness levels and emergency flash. C4 LED technology focuses light on objects hundreds of feet away! Photonic Crystal and Thin Film Flip Chip, among other technologies combine to make LEDs even better! Such enhanced efficiency as well as innovative use of reflectors to magnify, direct and intensify light beams.