This is the rail used for an authentic M4A1 block 2 straight rail build. The rails come in black or FDE. The black was not made by Daniel Defense for years. Some have come back in 2020 in a limited production. Black is perfect for a unique build or one that you are going to Cerakote or rattle-can for authenticity, and make it your own design.
All Daniel Defense RIS rails sold by Charlie's include all hardware (screws, barrel nut and color matching RIS hex-ring). Installation wrench is not included, but offered for sale.