The Sig Sauer BDX Combo Kit combines the Sierra3BDX Riflescope with the Kilo 1600BDX 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 1600BDX rangefinder via Bluetooth and set up your ballistics profile. After that, the whole system is ready for hunting or shooting. Features of the Sig Sauer BDX Combo Kit: Scope and Laser Rangefinder connect via Bluetooth Uses Sig Sauer’s Applied Ballistics Ultralight™ and LevelPlex™ digital anti-cant software systems to provide an accurate shooting solution to riflescope Features of the Sierra3BDX Riflescope: Weighs 25.9 ounces 30mm tube size 52mm objective lensEye relief: 3.43" high, 4.21" low Second focal plane Features of the Kilo 1600BDX Laser Rangefinder: Weighs 5 ounces 17mm eye relief 22mm objective lens Sig Sauer BDX Combo Kit, Kilo1600BDX LRF and Sierra3BDX Rifle Scope, 6.5-20x52mm SOK16BDX05