Complete any type of AR-15 Upper Receiver with these Completion Kits! Whether you have an old school retro slickside carry handle upper or a modern M4 flat top, one of these kits is the solution to complete your build. Each kit is specifically composed to include parts that are correct for a particular receiver, and no unecessary extras. Available in the following configurations: M16 Slickside - Meant for early M16 carry handle upper receivers without a forward assist and using an A1 rear sight assembly. Includes proper A1 ejection port cover. M16A1/C7 - Intended for later M16A1 and Canadian C7 type receivers, with a teardrop forward assist and an A1 rear sight ass Mfg: Brownells