Originally Posted By oldranger
I understand the 502 is a later model, with "improvements." If I had a 51, I wouldn't necessarily abandon it for the 502. i would say that ZL's entire line of lights is pretty impressive and that extra batteries are rather easy to carry along.


The 502 is an updated version of the 501. The most significant difference between the 51 and the 501/502 is a reflector which greatly improves throw at the expect of a very even flood. If I was just using a light around camp, the 501/502 is wonderful, but I didn't like it at all when biking or wayfinding at night.

As others have indicated, the .9H runtime at max is typically not an issue. I use it at this level for seconds at a time. When I am trying to figure something out and need to see a good distance. Normally the headlamp is running at one of it's lower settings.

--Mark