Description The BDX rangefinder and riflescope system is simple, fast, and intuitive. Simply download the ?SIG BDX? app available for Android or iOS smartphones, pair the KILO BDX rangefinder and SIERRA3BDX riflescope, set up a basic ballistic profile, and then you?re ready to shoot or hunt. Once you are in the field, range your target as you normally would, and the KILO BDX rangefinder will utilize onboard Applied Ballistics Ultralight to instantly send your dope to the scope via Bluetooth. Using your basic ballistic profile the ballistic solution is calculated for your target and will instantly illuminate on the BDX-R1 Digital Ballistic Reticle with windage and elevation holds in the SIERRA3BDX riflescope. A blue LED on the riflescope power selector indicates that the BDX system is paired, and when the reticle has received new ballistic holdover and windage data from the rangefinder. Firearms, trailers, and some accessories are only available for purchase in stores. Each location follows all BATF and individual state/county/city laws to insure the desired product is legal for sale. Any info provided online is subject to change, please go to your local store for more accurate information.