Some time back, I took a look at the LaserLyte FSL-3 itty bitty rail mounted laser. Now I'm doing the same with the latest/greatest version, the LaserLyte V4 Laser . There are a bunch of rail lasers out there, so it's really all about the features. With both these units, size is the key. Both the older FSL-3 and the new V4 are pretty much the smallest effective rail lasers on the market. In terms of taking up landscape on a weapon.... they just don't use much.
The V4 is slightly larger than the FSL-3, but not enough to make a big difference. In trade, it's edges have been rounded off and it's a very smooooth gadget, offering no nasty sharp bits to dig in while carrying. Like the FSL-3, the V4 has a feature I approve of greatly.... it is programmable for either a solid red laser, or a pulsing beam.
Personally, I find the pulsing beam to be a much quicker pickup to my eye. I just see it faster, and can align it to the target faster. That's a good thing, right?
Using the pulse beam also doubles battery life, a healthy 10 hours even with the tiny itty bitty little watch batteries this thing uses (LaserLyte includes spares with every unit!).
The V4 also maintains the auto-off feature of the FSL-3, giving a flickering warning of impending offness after five minutes of solid use.
I think LaserLyte has also made an upgrade on the adjustment system of the V4, since I found it dead easy to get a perfect sight alignment with it. Much easier in use than the FSL-3, which I found a bit persnickety in how it needed to be adjusted. Both hold adjustment... well..... forever, but the V4 was easier getting there to start with.
The V4 uses two activation buttons on the back of the unit. One on each side, so righties and lefties are both served equally well. For me, either are usable, depending on where my trigger finger is. When I mount the laser on the rail of my M&P 15-22, it's buttons fall under the thumb of my support hand.
What to use the teeny little rail lasers on? Well.... just about anything you want, I suppose. Being as small as they are, they just don't get in the way much. Given the right holster, use on a regular carry pistol would be perfectly fine. The Fat Man keeps one on the spare backup auxiliary house gun (more on that later), and another on the rail of his 15-22 rifle. Mounted on the rifle, it makes low light can busting in the backyard a ball.... and whoa betide the raiding raccoon who gets into MY trash cans!
For those on a budget, the very LaserLyte V4 is a reasonably priced, feature rich, and robust little laser that will work on anything with a bit of rail. Not overly fancy, and nothing to gloat over on the BBQ gun. It's just a simple working mans laser sight. I've loaned my M&P 15-22 to teenage boys for a week at a time, and they couldn't manage to break the laser unit. Now..... that's saying something about durability! I own a couple.... and glad of it. They are handy little buggers.