Works as intended - Trijicon Electro Optics Battery Extender

Not much to it. Just screw it on and you can use 3 cr123 instead of 2. It extends the run time for the ir hunter mark 2 by a couple of hours, so it will last for most of, if not all of a hunt. Simple to use. Just screw it on and change the setting in the settings menu from 2 batteries to 3.