"Single AA battery. Variable brightness and flashing/signalling (including SOS) modes on both the white and red beams (the picture shows two flashlights, but both red and white bulbs are built into each flashlight; you use one button to control both)."
"From the Amazon description: "The light shines up to 65 feet at a 35-degree floodlight angle. Additional features include continuous and flashing red light, and the light runs for 40 hours on a single AA battery. A narrow headband reduces packing volume, while still offering long-lasting comfort on your head, and the case weighs only 48 grams with batteries.""