The Black River Tactical MarkBlue Gas Tube is a premium quality gas tube used exclusively with the BRT PDW length gas system.

The BRT PDW gas system was created to provide OPTIMUM performance from 9" 5.56 barrels and is excellent for longer barrels in .277 WLV, 6.8 SPC and 300 BLK.

The BRT PDW gas system is longer than the Noveske Pistol length, but shorter than the standard Carbine length.

The distinctive "MarkBlue" dot allows easy identification of a genuine BRT gas tube and guaranteed performance.

It is compatible with BRT MicroPin Gas Blocks, front site bases and low profile gas blocks.