AR-15 Buffer Tube Kit Colors: Black Anodize Tungsten Anodize OD Green Anodize FDE Anodize MSRP: $54.99 Find A Dealer Features: The package includes an endplate, castle nut, and tub Anti-Rotational Castle Nut, no need to stake Crafted from Billet 7075 T6 Aluminum Built-in QD Slot on End Plate Anti-tilt BCG mechanism Maritime use in mind