Mounting to a Picatinny rail-The wide, 6-screw Tactical ring offers solid support for 30mm riflescope tubes. Scope Ring Heights are measured from the base of the ring to the center of the riflescope tube. Sold one ring per package. Mfg: Vortex Optics SPECS: One ring per package; 7075 T6 aluminum. Recommended torque range for Base Clamp Hex Nut 35-45 in/lbs, Ring Screws 15-18 in/lbs.