This Crimson Trace laser is installed on one of my main carry guns. It took me about 10 minutes to sight it in at the range and now it is deadly accurate. As small revolvers do not usually focus on sights, this laser is a welcomed addition and gives me confidence that if I ever have to use it in self defense - it will be right on target. I have shot the revolver many times and have never needed to readjust the laser or replace the batteries yet. If you have one of these guns, you need one of these lasers!