Ok if you're on a budget - Leapers UTG Mossberg 500 Picatinny Rail Mount

I bought this mount while shopping on a budget, and just needing to get a light on my Mossberg 500. This mount does get the job done, but because of the way it's built, it doesn't allow the light to be at a right angle to the bore, which is what I prefer. The mount is well built enough, so if you don't mind mounting the light at an angle, go for it. Or, perhaps you have a different application which would allow this mount to be of better use. However, for use on a pump shotgun, I would recommend the Laserlyte tri-rail mount also available from opticsplanet.com. The cost is considerably more, but it offers the user a much more modular mount with three rails at right angles from the bore, as opposed to one rail at an angle.
Pros: Inexpensive, simple
Cons: One rail, mounts accessories at an angle from the bore

This review was written in the old system and had content requirements that are different than reviews written today.