"The AIM Sports Mosin Nagant Tactical Tri-Rail Mount with Extended Rails gives you a 7"" top rail and two shorter side rails, all Picatinny and Weaver compatible. It is built of anodized aircraft grade aluminum. This Mount requires no gunsmithing and no drilling and tapping to install. The triple rail mounts to the rear sights of compatible rifles and gives you enough extra room to mount a longer eye relief rifle scope. Avoid ""scope eye"" with this Mount.|Accepts all standard Weaver / Picatinny 1913 accessories|No drilling, tapping, or gunsmithing required|Mounts to rear sight of models 91/30, M44, M38, M39 and Chinese 53|Allows mounting of long eye relief scopes to standard rifle|17 Mounting slots for flexible eye relief"