For those unfamiliar, the Solarforce L2 is what is known as a "P60 host" that takes a standard sized self contained "bulb" unit comprising electronic voltage control circuit, LED emitter and reflector. It just drops into the body of the torch and you screw the head back on. So you can change the characteristics of your light in a matter of seconds - or replace a damaged LED unit. One night I killed a Cree XP-G dropin that I was using on a shotgun - happily I'd packed another dropin in a 35mm film canister, and was back in action shortly thereafter.
The L2 comes in a variety of sizes and colours and battery configurations. The L2T is the newest, and is designed to take one 18650 Li ion battery or a pair of Cr123 or RCR123 batteries. The 18650 is the diesel engine of torch batteries, and that's all I use as I get really good runtime and just charge them up over and over with no ill effect.
The L2T is 132mm long, with a 32mm head and 25.4mm body - so scope rings will fit it nicely if you want to mount it to a rifle that way. Its body is made of 6061 T6 aluminum and it's anodised black with knurling here and there. The switch is a forward clicky, so you can push the switch in a little way for the light to come on momentarily, without having to lock the switch on. There are two rubber grip rings, which are removable. There is an O ring at either end of the torch and at the lens, for water resistance. The empty chassis is 87gr according to Solarforce's literature. These lights arrive in a bubble pack with cardboard backing.
This torch is compatible with Solarforce's Pro-1 monster thrower and Pro-2 monster flooder heads so the body can form the base for a bigger, more powerful light. Extension tubes for extra batteries can also be obtained. :onya: You can also change the bezel, the lens and the switch and there are remote tailswitches for these lights. Mine has already been fitted with a lanyard loop, a flush fitting stainless bezel and will be getting a glow in the dark switch boot.
Torch with a run of the mill Cree XR-E R2 emitter and smooth reflector. Wall is about four feet away.
So, what's to customize? Well, I've taken a few pics of what I did over the course of a few minutes using some of the dropins I had around the place.
Beamshot of the XR-E R2 emitter and smooth reflector. This makes a good general use, compact torch and is the setup I use for spotting foxes and other game. It also goes well on a .22 or airgun and will clearly light up critters at about 80m or so. Fox eyes show up a good few hundred metres off. These are around a 200 lumen unit.
This is a Cree XM-L unit, on high. It's an Ultrafire three mode dropin, and has been tested by someone on Candlepower Forums at around 900 lumens. It will light up half a footy field and is blinding at close range.
A red Cree XR-E. Not a long thrower but boy does it make critter eyes light up. This is a single mode, probably with around 150 lumens. My young bloke has a five mode in his light, and the strobe mode is blinding. Tested on our dogs and cat, it makes them head for the nearest exit.
Now, I've dropped a bubble shaped glass aspheric lens in here, in front of the XR-E R2. This makes a 150+ metre spot thrower and is similar to what focusable torches give on full focus. This will out throw the popular LED Lenser P7 on full focus.
Goes well as a compact thrower on a .17HMR or similar. The ugly Cree rings disappear after a short distance. This is a $2 lens. A good lens would be more efficient and you'd probably get a cleaner beam pattern too. 
Red LED with the same lens. I shot a few foxes with this the other week. Good for about 100m or a bit more. Can just as easily be blue or green too.
The torch with the XM-L on the left and the red XR-E on the right.
I had the torch out with me the other night, using the white XR-E R2. It went well, and the head doesn't even get warm running the little XR-E continuously. The big XM-L is another matter and the head gets very warm if the unit is running for 15 minutes. I heatsink the body of the dropin to the head of the torch with some alfoil wrapped around the dropin - this pulls heat away from the dropin itself and to the head and body of the torch and into your hand or the air. A hot LED loses efficiency and down goes the lumens coming out the front.
All in all, a very nicely made little torch, and upgradeable when new LED technology comes out. (and it always does....)
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