Leupold’s famous rotary dovetail rings in BOTH front AND rear bases; there’s no way a ring can shoot off its base. Ideal for large caliber, heavy kicking rifles that can throw a scope off easily, plus light caliber varmint rifles that need an absolutely rigid scope mount to make full use of the gun’s accuracy potential. Dual Dovetail Bases and Rings must be used together; will not interchange with other Leupold rings and bases. Rings and bases sold separately; select the correct base set for your rifle, then choose rings.Those marked “Rev. Frt.” have reversible front base to help get correct ring spacing. SPECS: Steel. Finish: Standard Std. and PB, polished, blue; Matte, matte, blue; Silver, matte.