We have been manufacturing rifles for 6 years and because of the recent bankruptcies of some manufacturers in the United States, we have been forced to take manufacturing of muzzle breaks into our own hands.
This product vanished a year ago and we LOVED them.  We still had one in stock so we made our own.  There are currently only 2 models.  It is 7" long and in a backdraft angle or style.  It weighs right at 15 oz (heavy) for a purpose.  We will have some videos up soon to show on our website but you can do a lot with this muzzle break, especially in small calibers. 
Please look at the 18guns or Security AllStar website for more.