Colt LE901/CM901 Adapter Block Conversion Kit (SP99415) — Mil-Spec 5.56 Upper Adapter
The Colt LE901 Adapter Block Conversion Kit is built to convert Colt LE901/CM901 .308 (7.62x51mm) lower receiver assemblies for use with a Mil-Spec 5.56x45 NATO/.223 Rem upper receiver assembly. The adapter provides a .250" pivot pin interface to mate the upper to the 901-series lower.
This kit includes the adapter block, buffer, action spring, and conversion kit manual.