You can find the Spike's Tactical R2 Muzzle Brake 5.56 here Fast $9.95 shipping! Orders over $200 ship for free!

The Spike's Tactical R2 Muzzle Brake is designed to reduce recoil and barrel rise, allowing for faster and more accurate follow up shots.

Caliber: .223/5.56
Threads: 1/2x28 TPI