Mancraft M4 BodyDescription Developed and manufactured by Mancraft, this M4 body consists of an upper and lower receiver that was pre adjusted to accept HPA conversion kits. The upper and lower is precisely CNC machined from high quality 7075 T6 aluminum alloy and anodized black to minimize scratches and external physical damage. The lower receiver accepts TM standard and Mil Type buffer tubes. The set also includes the trigger, dust cover, bolt catch release button,