Aero Precision APAR600103: The M4E1 Complete Lower Receiver is the perfect base for your custom AR15 build. This complete lower features Aero Precision\'s M4E1 Lower Receiver and is upgraded to include a Magpul MOE Grip and STR Stock. Includes: M4E1 Stripped Lower Receiver - Anodized Black Magpul(TM) MOE Grip - Black Magpul(TM) STR Stock - Black Mil-spec Lower Parts Kit Carbine Receiver Extension AR15 Carbine Buffer and Spring These parts are installed