FENIX HM23 HEADLAMP 240 LUMEN The Fenix HM23 is a compact and ultra-light headlamp with runners and hikers in mind. The HM23 weighs just 1.52 ounces and is powered by a single AA battery that provides 8 hours of life on the highest setting. The flashlight is turned on with single switch operation helping you keep your eyes on the trail. The headband is reflective and can be seen from 164 feet away. The light beam is adjustable up to 180° making it usable for a variety of activities.