The Buffer System for Revolution Firearms and Rogue Firearms is proprietary.

The Bolt Carrier Group (BCG) on the Revolution PD, Revolution DI, and Rogue, requires a longer stroke in order to eject .308 WIN cartridges from the Upper Receiver. 

Because of this, these firearm models use a proprietary (longer) Buffer Tube as well as a proprietary Buffer Spring.

STANDARD LENGTH AR15/M16 CARBINE BUFFER TUBES (RECEIVER EXTENSIONS), AND BUFFER/ACTION SPRINGS WILL NOT WORK IN THE REVOLUTION PD, REVOLUTION DI, OR ROGUE MODELS. DO NOT USE THEM, THEY WILL NOT WORK, AND YOU MAY DAMAGE YOUR FIREARM.

Download/view the file below for a visual representation of the correct Buffer Tube and Buffer Spring.