OP M6 65Lm Xenon Tactical Flashlight & Red Laser Sight Black
[AS3574]

Laser does not have spring assisted, shimmed, or quad adjustable beams it only has a lower and right adjustment. What does this mean? It means that you're not going to be able to calibrate this thing unless you take it apart and shim it... Not real hard, however; the screws strip when you do it, they're just screwed into the plastic case and the plastic comes out with them...

After an hour and a half of work I've got it to lined up on my KWA G18C, but there are cheaper alternatives that do not require this much work.