KNIGHT'S ARMAMENT QDSS NT-4 PRG 5.56MM NATO RIFLE SUPPRESSOR Recent advancements in suppressor design and manufacturing have enabled KAC to update the venerable Quick Detach Sound Suppressor (QDSS) NT4 suppressor with both Pressure Reduction Technology (PRT) and KAC's patented Purge (PRG) flash reduction. Maintaining the same attachment mechanism and form factor as the legacy QDSS NT4, superior pressure reduction capabilities are added without sacrificing performance or durability. Potential noxious gases from the rifle being fired are pushed forward of the operator, reducing potential exposure and increasing comfort when firing. First round flash is significantly Mfg: Knights Armament