($220 MSRP, but $185 at Amazon)
The Center Mass Laser (hereafter known as CML) mounts easily to any Weaver or Picatinny rail, and a hex wrench is conveniently included.
The laser is offset enough to mount behind iron sights, and a variety of activation options (tape switch momentary on/off, button momentary on/off, and double press for constant on) mean that it can be operated from essentially anywhere it can be mounted.
To sight in the CML, simply aim at the desired point of impact and then adjust the center dot until it is where you want it. I used a 12 gauge bore sight laser to get mine lined up before taking it to the range for patterning** and fine-tuning, but if you have a reflex sight, red dot or other optic already zeroed, simply adjust the CML to that optic's reticle.
Like most lasers, there is no definite feedback system or locking adjustment like a scope would have; adjustment is via set screws and is performed using the "Well, that feels about right, let me take another shot and see if it works or if I need to move it again." I'm not fond of this, but I have yet to see a laser that has adjustment screws similar to MOA clicks.
* This is because my shotgun is set up for home defense, where a shorter barrel and wider choke give optimal results. For hunting or shooting skeet or trap, I would use a longer barrel which gives a tighter pattern and longer ranges. For those wishing to learn more about choke and spread, visit these two pages and look at the diagrams, or watch this video for a simple compare & contrast.
**For people who are not familiar with the jargon, patterning a shotgun is where you take it to the range and shoot it to make sure that it's hitting where you're aiming. It's much like zeroing a scope, except for the fact that shot is nowhere near as accurate as a bullet. That's why it's called a "pattern". For more information, watch this video.
smaller version of this laser and mounted it to my mother's PMR-30. Mom has notoriously poor eyesight, but the ring of red laser light is easier for her to see, and makes target acquisition faster, than a single laser does.)
LaserLyte says that the pattern grows at one inch per yard, but I'd like to put that into terms that are a bit more helpful.
Using a sheet with one-inch squares on it, I put the muzzle of my shotfun against it. At that range, the circle was less than one inch across. Considering that 12 gauge equals .73 caliber, this is logical.
I then measured the distance between my front door and the wall closest to the kitchen door, i.e. where I would be standing if I needed to shoot someone breaking in. It was 20 feet, and the ring of green now measured roughly six inches across.
(Yes, math types, I know that 20 feet comes out to 6.7 yards. However, the laser wasn't mounted to the wall, it was mounted to the shotgun which is forward of the wall. The actual distance from laser to wall was likely 18.5 feet.)
After that, I took my shotgun to an outdoor range to see how the ring spread matched the patterning of the shotgun. I set up a sheet of white paper at a distance of nine yards, with the intention of moving the target further back once I had matched the pattern to the point of aim.
However, at that range, the green ring completely filled the sheet of paper! ("Negative, Ghost Rider, the pattern is full.") And yes, the shot pattern of both birdshot (used for testing) and buckshot (used to make certain it was where I wanted it, confirmed with larger holes) also filled the target sheet nicely.
Only one thing disappointed me: despite being a very bright green laser, the light was very hard to see in the bright Florida sun. I was able to see the center dot by sweeping the target and looking for movement, and after that I was able to see the rings, but it was by no means a quick target acquisition.
This is not a fault of the product itself, however. Lasers are famously hard to see in bright sunlight, and a red laser would have been completely washed out. My only solution for a situation like this would be to switch to a reflex sight or green dot optic. Given the small profile of the CML and its ability to be mounted nearly anywhere, mounting an additional optic if necessary shouldn't be a problem.
Other Things I Like
Not only does it operate from a reasonably easy to acquire CR123 battery, the battery cap is also tethered to the casing. This makes battery changes "in the field" much easier and with less worry of losing the cap. In addition, it comes with clear instructions, a hex wrench for immediate mounting, and an already charged battery.
My Rating: A+
I like this product very much. It has certain limitations, of course, but its usefulness outweighs those. It's not ideal for most sporting activities, but in home-defense situations it absolutely excels. As an inexperienced but enthusiastic shotgunner, I especially like being able to see at a glance what my shot pattern will be.
It's expensive, but if you can afford it and use a shotgun for home defense, I cannot recommend it highly enough.