Made in the USA, San Tan Tactical PILLAR Truss Pockets for increased structural rigidity. It is cut from a single billet Of 7075 -T651 aluminum with a shell deflector, machined in T markings, M4 Feed Ramps, and is machined to Mil-Spec standards. The upper is able to interface with all AR15/M16/M4 weapons systems and accessories. It is also compatible with all known battery assist levers. The STT-15 Lite Pillar does not include port door assembly.