That looks a whole lot like what I have. Becarefull with the power leads to the circuit. I had some trouble with wire breakage. No real problem, but tight soldering!

When you get it/'em (I' suggest one more than the one for each application/tank), hook up power, lay on a flat surface (table), with the dot hitting a dark, flat surface about a foot or more away, roll the diode housing forward and backward and look for the dot's trace drawing a circle. Mark the high point on the front of the laser housing with a sharpie. It will help later when you mount and try to collimate (align or aim) the laser to the canon bore.

good hunting!

Splat