The X-TRAC connects via Bluetooth to your ATN Smart Device and controls all the features and functions without touching the scope. The X-TRAC makes the process of menu surfing and digit input faster and easier, manipulating the user interface and other features has never been easier or faster, by using the scroll wheel and 6 tactile buttons. You can use the X-TRAC to adjust the magnification in the scope with a simple action. Using your Ballistic Calculator, Smart Range Finder, Environmental Adjustments and other cool features on your Smart HD Scopes just got easier. The X-TRAC buttons lets you take photos and videos without the need to move your hand from your weapon. The X-Trac uses one CR2450 battery and attaches to your gun with two Velcro straps.