This picatinny rail base fits the Ruger Mini 14 , NOT the newer Ranch rifles. All mounting hardware included. Rails are machined from billet 6061-T6 aluminum and black anodized. Any Weaver type rings may be used. Can be mounted to rifle without drilling and tapping, however it is preferred to have a gunsmith drill and tap one 6-48 hole in the front of the receiver. This makes an extremely solid mounting system. But if you prefer to use the non gunsmithing method simply remove the rear sight and install the Rail using the existing holes in the receiver. Then tighten the 10-32 set screw in the back end of rail against receiver to force the front of the rail down against the front of the receiver. These Picatinny Rails are machined to fit the 181 series Mini 14, serial numbers that begin with 181 and higher. If you need a rail for the 180 series, serial numbers beginning with 180, these are available as well but you need to specify as they are different.