The L1 offers bright LED lighting using just 2 AA batteries, making it lightweight and comfortable for extended use. It offers multiple light mode settings; ultra-bright, bright, power-save, and emergency strobe. When the battery life reaches 15%, the headlamp automatically switches to the power-save mode. The unique circuitry and cooling fin design will prevent overheating of the lamp. It delivers a narrow beam spread.
At its brightest setting it will operate for 8 hours on one set of batteries, projecting its beam from 32 to 35 meters (105 to 115 feet). In its "power-save" mode it will operate for 85 hours, projecting its beam 10 to 11 meters (33 to 36 feet). Brunton measures the maximum distance as the point where the light level still exceeds 25 lux, which is roughly equivalent to the amount of light cast by a full moon.