The BMD, (Blast Mitigation Device) is a unique blast shield that allows the muzzle brake contained inside it to continue to function as normal with regard to muzzle climb mitigation.
The patent pending design features unique 'through' ports that connect the muzzle brakes vertical vents to the outside atmosphere. This feature allows the brake to function while within the device unlike other system that alter the way the original device works and inevitably remove or massively reduce efficiency. The device also features sets of 'diffuser' grids positioned towards the top of the blast shield that assist in allowing gas to vent upwards as well as forwards at the time of firing, assisting even further in muzzle control.