Amer.Def.Recon-x 30mm q.D.Scope mount 3" offset FEATURES:-American Defense Recon-X 30MM QD Scope mount -3" Offset -For 1" picatinny rails -Black Matte finish -Aluminum alloy material -Type of rings needed: None-integral -QD auto lock lever system made in specialized factories features 3" offset for extended eye relief designed for flat-top ar-15's Other Features: Qd auto lock lever system made in the usa features 3" offset for extended eye relief designed for flat-top ar-15's ring size is 30mm