It's worth noting that this is a Henry S. design. For the last 10-15 years his lights have been the best you can buy. He generally does one light for a company then moves on, so where you find his lights varies. Right now he's in business for himself at HDS Systems.

The more important thing is just how tough this light is. Breaking one without tools is nearly impossible. It's expensive, but when the difference between having light or not is home-alive or dead, Henry's lights are the choice. If you have the cash there's nothing better, just almost-as-good.

(Henry is a caver)


Alas, an alkaline 1xAA can never be as bright as a 1xCR123: that AA simply can't produce as much power.


Look for the words "Cree R2" in the specs for a light. "R2" is the magic part. There are also the -WC bins, but I don't know the bin ID's to look for.

Unfortunately I don't know of any top-tier manufacturer using the R2 for mainline lights. It's Chinese makers (who may be using -WC instead of R2 to save money) or specialty lights like the Draco.


Sadly this isn't practical except in very general terms. Different makes of batteries behave quite differently, even within the same type of chemistry. Each basic type of battery (alkaline, NiMH, Lithium of various flavors) work in different voltage ranges with different discharge rates.

The best you can do is detect a nearly-discharged battery, and even then there are gotchas: the Notvatac doesn't do this right unless you install a new or fully-charged battery.

For an emergency light there's a lot to be said for a direct-drive light using an old 1 watt Luxeon emitter on a 3 D-cell with alkaline batteries. These are nearly extinct now but just about ideal for survival uses: turn it on and a _month_ later it's still producing enough light to walk a dark trail at night.