The Sig Sauer SIERRA6BDX 3-18x44mm Riflescope is built using SIERRA3 award-winning technology plus the Sig Sauer BDX Ballistic Data Xchange technology. The Sig Sauer SIERRA6BDX 3-18x44mm riflescope gives the hunter or marksmen an intelligent auto-holdover specific to their ballistics, target, and environment. Pairing this scope with a Sig Sauer BDX equipped rangefinder allows the shooter to bring the capability of Applied Ballistics into the field without the need for a mobile phone. Thsi scope includes a digital focal plane as well as the BDX-R2 reticle. It mounts to your rifle using 30mm rings.