I hunt, sometimes work night shift security, camp, hike, etc. I like a pocket light when I am at the range because I can shoot till 930pm and that sometimes pisses the range neighbor off. I shine it from 100yards to ensure no one is waiting for me at the shoot shack when I am walking up the hill. I take a light with me when I know I will be out all night. Also, walking the dog at night the deer tend to hang in the empty fields and don't much like the dog.
Have you looked at the M2R Warrior? It has a tail switch that always goes on in turbo, and a side switch that can directly access moonlight mode independently of the tail switch. It also has a reversible pocket clip. It was the prefect mix of tactical and EDC light for me. If you're willing to spend a bit more money, Vinh over at www.skylumen.com will put pretty much any LED you want in one.
As long as the light can handle the 8.4 volts that a pair of RCR123As / 16340s will put out when fresh off the charger. Unless you meant to specify that he get LFP/LiFePo 3.2 V rechargeables. Most Surefires won't handle over 6.5 volts. Most of the nicer Chinese made lights like Olight and Fenix will run equally well on a single 18650. A single cell is safer than running a pair of lithium batteries in series anyway.
I'm all for recycling, but there's no way I'd take the risk of running cells that old in a high drain, modern flashlight like the OP is looking for. I'd be surprised if a 10 year old battery could maintain the sustained current draw that some light demand in high and turbo modes. I think it's a little reckless to recommend this kind of stuff to someone who's this new to lithium batteries. It sounds like the OP is a long way from buying even relatively low cost test equipment to ensure safety with recycled cells.
You may wish to do more research. 3.6 to 3.7 volts is the nominal voltage, but they're 4.2 volts when fresh off the charger. Almost all high quality chargers use 4.2V as the cutoff voltage for a full charge. Some have the option to discharge back down to 3.7V for batteries that the user intends to store. Most protected devices, or batteries with their own protection circuit, use 2.5 to 2.7 volts as the cutoff voltage at the other end to prevent over discharge.
I'm sorry, but those are not good lights at any price. They're water resistant, but they don't give you an IP water resistance rating. Their website specifically says that the light can be used in rain or snow, but not submersed. They claim 5,000 lux, but they don't state at what distance that measurement was obtained. 5,000 lux at 1 meter is equivalent to 5,000 candela (cd) at 1 meter. If we're using the ANSI / NEMA FL1 standard, which atomic beam doesn't use, we could compare things apples to apples. The Atomic beam light doesn't include a battery, and the plastic zoom lens has low light transmittance. Atomic beam claims to use a Cree LED, but they don't specify which one. The Atomic Beam is just a repackaged version of the generic Chinese zoomie light, sold at a very high mark up. You can get the same lights for half the price or less on Amazon. If you're willing to buy direct from China through a site like Ali Express and wait on shipping, those lights can be had even cheaper.
That's been my experience as well.
That's the one that was stolen that I am trying to replace. Nice light just looking for something a little brighter.
