This flat top upper receiver is a perfect start for your AR build, from a standard M4 style rifle to a 300 Blackout hunting upper. This upper receiver is the perfect foundation. Built with M4 feed ramps which line perfect with Our barrels and many more. Made from 7075 aircraft aluminum to milspec. These anodized forged uppers will stand up to the abuse these rifles are known to take. This upper does include includes forward assist and dust cover.