Monstrum Laser Sight System with Picatinny Mount for Mossberg 500/590/835/930/Shockwave Series Shotguns | Green Laser Sight

Super easy to mount. Don't forget the blue Loctite! Use the supplied large Allen wrench to open the compartment on the front of the rail. The instructions show to open where the power switch is. Use some common sense! It also couldn't hurt to have extra batteries in stock. It uses two 1/3N batteries. The green laser is super bright in day or night. Zeroing in was a breeze. Picatinny rail is nice quality and not cheap plastic. Looks great. Feels great. Now I know this Shockwave is going to be spot on every time!

Parasitic battery drain: I must be one of the unlucky ones. While I see several outstanding reviews, there area few 1 star reviews and I will be adding mine to that category. There is some type of occult parasitic battery drain that results in a dead battery when the gun is put in storage. Like others, the 1st time it happended, I thought it must be my fault? I must have left it on. So second time I was very careful to be certain it was off, after testing it, and yet it still drained in about 2-3 weeks. I then (yet again) put in new batteries, confirmed they worked, but then removed and reinstalled the batteries without testing them. They lasted for months and months and were working fine when I did actually need to take the weapon from the safe and use it. Once tested, however, they too failed (drained out) in 2-3 weeks. Seems the only soultion is to NOT test the batteries, or insert them - but that just means the weapon is NOT ready at a moments notice - which OBTW - is the reason one keeps a weapon.

Very nice quality and great idea to put a Lazer built in to a rail and high quality to

Bought this for my daughters 590 after she heard "activity" in her back yard rustling in the leaves. The fit was excellent and it does not move or shift during firing. The install took under an hour as I was teaching her to do it, but I could have done it in under 30. The quality is rugged and firm, nothing cheap here at all. Durable. The beam is plenty bright and can be seen for at least 1/2 mile.

It works and fits well. All needed tools included and even batteries. Laser tag is bright and was easy to adjust. My only knock is I wish the laser was on the right instead of the left. With the left placement, the laser can easily be obstructed when your left hand is on the shotgun forend. When racking the slide of my .410, I must be aware of my left hand placement to avoid blocking the laser.

The batteries drain when not using. So when you first put the batteries in it works great. It's easy to sight in. However the next time you go to use it. Say a few weeks later it won't work because the batteries need replaced. I can't figure out why there would be a drain when not in use. However, there is and for that reason this laser sight it junk.

I had issues with this product. It used batteries up quickly while sitting idle and quit working altogether in about 8 months. The seller made contact with me promptly and sent a replacement item. They stood behind their product and made things right. Very happy with the whole experience.

Item fit perfectly and operates the way it should