Samson Manufacturing Corp., Rapid Precision Mount, 30mm, Black Lightweight design 1/2" Steel cross bolt thumb nuts Dual steel recoil lugs integrated into cross bolts The Samson Rapid Precision Mount (RPM) features a lightweight design that doesn't compromise on durability or accuracy. Precision machined from 6061-T6 aluminum, these scope mounts are perfect to mate your favorite optic to your favorite firearm. Integrated into the clamp cross bolts are two steel recoil lugs to eliminate scope base movement during heavy recoil to better maintain zero. The scope ring bases utilize threaded steel inserts to prevent the internal threads from being stripped by the ring cap screws, extending the lifespan of the rings if you decide to change out the optic.