The Zebralight H54c N Neutral White High CRI AA headlamp has a maximum output of 245 lumens from the Nichia 519A-V1 LED and is powered by a single AA battery (NiMH, lithium or alkaline). 

The H54c N has three main brightness levels (High, Medium and Low), each of which can be programmed to one of its two sub-levels. The second sub-level of each of the main levels can be further programmed to different brightness levels. 

The head torch features a basic operation system to activate the three main levels. One short click turns on the light to High and click again to turn the light off. Press and hold the switch for about 0.6 seconds to turns on the light to low.

For more advanced operation and to configure the light, short click to turn on the light to High and click again quickly to cycle from High to Medium to Low. Press and hold to cycle from Low, Medium and High, release to set. Double click to toggle and select between the two sub-levels for that main level. Sub-level selections (except the strobe) for the 3 main levels are memorised after the light is turned off and through battery changes.

The second sub-level of each main level can be configured after 6 double clicks. Double click (starting with the 7th) to cycle and select different brightness levels or strobes. Short click to turn off the light when finishing configurations. The selections for the second sub-levels are memorised after the light is turned off and through battery changes.

Brightness Levels:

High: H1 245 lumens, 1.3hrs runtime or H2 203 lumens, 1.7hrs runtime / 160 lumens, 2.1hrs runtime / 105 lumens, 3.5 hrs runtime
Medium: M1 57 lumens, 6.5 hrs runtime or M2 16 lumens, 30.6hrs runtime / 8.3 lumens, 2.8 days runtime, 3 lumens, 6.8 days runtime
Low: L1 0.9 lumens, 18 days runtime or L2 0.22 lumens, 1.9 months runtime / 0.06 lumens, 3.3 months runtime / 0.02 lumens, 5.2 months runtime
Plus Beacon Strobe Mode: 0.2Hz Beacon at Low/0.2Hz Beacon at H1/4Hz Strobe at H1/19Hz Strobe at H1

Waterproof rating of IPX8.

Includes: Pocket Clip, Two O-rings, One black silicone holder with headband and One AA alkaline battery.