Great laser - ArmaLaser Laser Sight for S&W

This is my 2nd Armalaser, the first is for a Glock 42. I love the fact that you do not have to press a button or rely on a holster to turn it on. Simply by holding the gun by the grip activates the laser. It is a very bright green laser and easy to see. While the battery does require a tool to replace it, the unit does not have to be removed to replace the battery. I think this is a great design and highly recommend it. The down side is that the availability of cheap holster specifically made to fit the Armalaser is limited but there are still lots of fine choices.