The Zebralight H503c flood headlight has a maximum output of 284 lumens created by the Samsung LH3510 neutral white LED and is powered by a single AA battery. 

The head torch offers 3 main brightness levels; low, medium and high, plus beacon and strobe. Each main level can be programmed to one of its two sub-levels. The second sub-level can be further programmed to different brightness levels. All levels can be accessed using the durable electronic soft-touch switch.

The H503c has a precision machined unibody casing made from premium grade aluminium with a natural hard anodized finish. 

Brightness levels and runtimes

High: H1 264 lumens - 0.9 hrs or H2 220 lumens - 1.6 hrs / 158 lumens - 2.3 hrs / 97 lumens - 4.2 hrs

Medium: M1 52 lumens - 8.5 hrs or M2 24 lumens - 21 hrs / 9.6 lumens - 41 hrs / 3.3 lumens - 4.5 hrs

Low: L1 1.0 lumens - 13 days or M2 0.25 lumens - 1.1 mth / 0.06 lumens - 2.2 mths / 0.01 lumens - 3.3 mths

Beacon Strobe Mode: 0.2Hz Beacon at Low / 0.2Hz Beacon at H1 / 4Hz Strobe at H1 / 19Hz Strobe at H1

Includes: Headband, pocket clip, O-rings, 1 x alkaline AA battery.