The Sig Sauer BDX Combo Kit combines the Sierra3BDX Riflescope with the Kilo 1800BDX Laser Rangefinder to produce a set up that insures your shot will hit its mark and give you a clean kill. The riflescope and laser range finder work in conjunction via Bluetooth connection. The on-board software utilizes Sig Sauer’s BDX ballistics calculation system, that takes into account your rifle’s ammunition type, windage and distance to the target to calculate a shooting solution. The result of this calculation is then transmitted to the Sierra3BDX riflescope, and a holdover point will illuminate in the recital. Using the BDX system is fast and easy: download the “SIG BDX” app onto an Android or iOS smartphone, pair the Sierra3BDX scope with the Kilo 1800BDX rangefinder via Bluetooth and set up your ballistics profile. After that, the whole system is ready for hunting or shooting.