That's a Laser 301, or one of its variants. The diode has LED'd. I've had a couple of these lasers LED on me after only light usage, they seem to be prone to it if you're not careful. The heatsinking in these units isn't very good.
They're interesting units due to being a dichotomy of really smart and really stupid design.
The host style is my favorite, by far. I can't imagine anything ever beating it. It's solid and can handle getting knocked around, it looks good, and it's very easy to carry and use. The focus is adjustable. The inclusion of a keyswitch is an excellent feature, it prevents accidental activation while being carried in a pocket, especially if more than one laser is carred in the same pocket. They accept both 18650's and 16340's. With a good brand of 18650 they go forever between charges, with a 16340 the run time is still very good. The external design is almost flawless (IMHO).
However, internally it's a completely different story. The internal design is utterly stupid in nearly every way, nothing good can be said of it. For example:
1) Adjusting the internal lens focus is difficult to impossible depending on the variant. If you're lucky, you can use a screwdriver to turn the barrel, that is, if you can get the screwdriver through the front aperture. If you're unlucky, you either can't, or else the adjuster is one of the really stupid kinds that just has two little holes. God only knows what the proper tool is for those. You can use a pair of tweezers to adjust it but it's clunky and doesn't work very well.
2) The lenses themselves are garbage and will instantly be destroyed by any cleaning attempt beyond compressed air. If they get scratched or otherwise damaged, they are non-standard size, are not available separately, and thus cannot be replaced.
3) That focusing knob on top? It screws on. Sounds simple, doesn't it? But no, if you want to get it off, maybe because the internal lens is out of focus, you have to turn the knob left until it stops, then apply extra force to get the actual knob off. Only, in doing so, you jam the focus mechanism tight. To un-jam it, you have to put the knob back on and force it right until the focus barrel releases. Only, now you've jammed the knob all the way down onto the focus barrel. Most likely, turning the knob all the way down will put the laser past its focus point, assuming you can turn it all the way down at all. More than likely the focus barrel will collide with (and jam against) the main host body. It is basically a BITCH to get the knob part off and have the focusing barrel still free. F***ing IDIOTIC, there is no other way to describe it.
4) Very poor heat-sinking, the module is way too small. Plus, it's covered in plastic, which is an insulator.
5) Thread-locker, everywhere. Way too much. I needed to use a large pair of pliers and a pair of channel-locks to get them apart and even then it took a large amount of force. The diode module is glued in and is basically impossible to remove without destroying it.
5) They use a lot of non-standard parts that apparently can't be purchased individually. Good luck if you want to fix something that breaks, unless you're willing to have a someone (e.g. forum member) machine you a custom part. The lens barrel is the worst, it's a stupid 10mm or other imbecile size that isn't available anywhere. The actual lens itself is also non-standard, sorry, the lenses you see sold on websites won't fit. If you thought you could just knock out the bad lens and replace it, joke's on you, because you can't. Which sucks, because the lens is so poor quality that even an optical cloth will gouge it up, even if you blow it off with canned air and use proper lens cleaning fluid. Stupid, stupid, STUPID beyond words!
If it LED's or you ruin the lens IMHO just knock ALL of the internals out, throw away the focus mechanism, and get somebody to machine you a custom front end that will take a standard Aixiz module and still fit the host. Then just build yourself a new laser out of good-quality, standardized parts. That's what I'm going to do with mine, because at least I can maybe do that. Simply replacing anything is IMPOSSIBLE.
That having been said, sometimes Laser 301's do tolerate severe over-use. I accidentally ran my only violet remaining 301 for 10+ minutes earlier this evening, and it survived. I rigged it to use a Skylaser interlock tailcap and was observing the beam at range, then got distracted by something. I had taped the button down and was using the interrupt pin/wire thing to turn the laser on and off. Probably a close call, I'm actually rather amazed it still works.
The hosts that Lazerer uses for its LZCS line look and function the same as Laser 301's but internally they are somewhat different. (I use Lazerer as an example of this host type only; electronically I think they're fine and have had no problems with them). I've seen the empty hosts for sale on other websites so I assume the hosts themselves are generic. The focus adjuster looks like the same stupid design, but the lens barrel *appears* to be a common 9mm type (although I don't dare try to find out or otherwise mess with it, for fear of being wrong). The diode module is a bit more massive, has a heatsink (albeit a small one) and can be removed from the laser intact without a great deal of trouble. But overall I still think they are dodgy to work on, just not as bad as the 301.
Well that was longer than I intended, but bottom line: They're inexpensive and work really well, for as long as they do work. When they stop working, they are not easily fixable, due to poor internal design.
