C-Light Life Preserver Signaling Emergency Light Lightweight, waterproof design attaches easily to life vest or jacket with stainless steel pin or integral lash loops and Velcro strap. Intense incandescent light visible for up to two miles, depending upon conditions. Lens intensifies light 20 times brighter than comparable products. Operates on 2 "AA" alkaline or 2 "AA" 1.5V lithium batteries. Operating life: 8+ hrs. continuous @ -1 C. (30 F.). Complies with SOLAS; USCG approved with alkaline or lithium batteries.