Ruger Mini 14 Scope Mount New! Sun Optics USA P/N SM4506 Sun Optics USA P/N SM4506 Fits 181 series or later. Installs by replacing the bolt stop cover plate. Mounting Instructions and all necessary hardware instructions included. Made of 6061-T6 aircraft grade aluminum. See under type allows use of guns sights. Picatinny style rail allows more eye relief than simular mounts. Attaches by a single knob to the threaded cover plate. Stainless steel finish. Lifetime warranty by Sun Optics USA.