Same OEM rail sections that come with the OBR.
These removable MIL-STD-1913 Picatinny rail sections for either OBR 7.62 or OBR 5.56 are for those who want to replace damaged sections, or add additional rail space for grips, lights, etc. on their OBR. They simply attach to the threaded inserts using the supplied hex-head screws. Each section comes complete with hex wrench and mounting hardware.