You can find the Phase 5 Fatman Hex Brake 5.56 here.

The Phase 5 Fatman Hex Brake for 5.56 has 2 large baffle sections to deflect gases and reduce the overall recoil felt by the shooter. The two top ports are machined at a 20-degree forward angle to direct gas in a manner that helps with barrel rise. In addition to being a muzzle brake and a compensator, the Fatman Hex has great styling. Includes (1) crush washer.

Specs:

• Caliber: .223/5.56
• Threading: 1/2x28 TPI (Threads per Inch)
• Mil-Spec Black Parkerized finish
• Length: 3"
• Width: 1.26"
• Weight: 6.1oz

Note: APPROX. 1.35 FROM BARREL CROWN WITH CRUSH WASHER INSTALLED. IF YOU PIN ON A 14.5" BARREL, MAKE SURE THE BOLT FACE TO END OF BRAKE IS 16.000" UNLESS TO ARE MAKING A NFA REGULATED WEAPON.