The RRD-360HD is designed specifically with short barrels and high pressures in mind! Due to excess pressures/gasses associated with rifle calibers in short-barreled firearms, a barrel length restriction was put in place for many of JMAC’s popular devices. To remedy this, they've taken the 360 design and reinforced the device by adding additional material where it's needed and removing material in some areas to cut down on size, and weight. You get the same amazing performance out of their 360 devices, now with a Heavier Duty design for short-barreled firearms!
The X37 Series Muzzle Brakes combine the effective RRD muzzle brake design and a direct thread mount for several popular suppressors as well as the BDS-37 and BDS-37-EXT blast shield. This allows you to leave the muzzle device installed and simply thread the suppressor over. This reduces weight, length, and cost compared to QD systems. Direct thread is also the preferred mounting method for accuracy!