Forward Controls Design Xeno Thread Protector Black. Shallow and widely spaced flutes have been incorporated as coarse serrations. The flutes run partially along the TPM Xeno's length and are open at the muzzle facing edge to maximize their effectiveness as serrations. We didn't spend a single minute on aesthetics these flutes are functional and purpose driven we had no plans to have TPM Xeno match either our flash suppressors or brakes. If they happen to look good it is not by design we do like happy even though unintended consequences. Specifications for Forward Controls Design Xeno Thread Protector: Manufacturer: Forward Controls Design Color: Black Fabric/Material: 4140 Steel Finish: Nitride Package Contents: Forward Controls Design Xeno Thread Protector Forward Controls Design TPM-Xeno: Xeno Thread Protector Black