I bought this from muzzle brakes and more last year for a build I was putting together. I didnt end up using it because the thread pattern is too small, I wanted 9/16x24 but I ended up with a 1/2x28 i think. I never checked until many months later when I had all the parts together and by then I didnt want to bother returning or exchanging. Its .750 dia 4 ports with 1/2 x 28 thread pattern. It obviously has never been used or fitted, its exactly as would come new from muzzle brakes and more. Will sell for 35 shipped, I do paypal or MO. price is the same.