One of the most powerful of the low cost laser sight - Fire Field Green Laser Sight

These are the strongest green light lasers I have found at a reasonable price. They are a little more difficult to adjust the beam since you are adjusting all four quadrant alignment screws. You have to be careful not to over tightened the adjustment screws, however, they the stay adjusted once setup. They produce a strong light and come with two types of mounts plus a pressure switch. They are tough to beat for the price. These are made for shotguns or rifles, i.e. too large for most pistols.