The KAC QDSS NT4 legacy suppressor is a 5.56 NATO rifle suppressor originally developed in the 1990s and fielded extensively by the U.S. military and allied forces. It represents the original NT4 pattern and is engineered around the QDSS mounting system, providing a robust, repeatable attachment method for duty and service rifles.

This suppressor interfaces with QDSS-compatible muzzle devices, including the M4QD flash hider, M4QD MAMS, and Triple Tap compensator. This example includes a 1/2x28 M4QD flash hider kit for direct installation on standard 5.56 barrels. The NT4 legacy design emphasizes durability, alignment consistency, and sustained performance under prolonged firing schedules.

Specifications

• Manufacturer: Knights Armament Company

• Model: QDSS NT4 (Legacy)

• Caliber: 5.56 NATO / .223 Remington

• Mount Interface: QDSS system

• Compatible Muzzle Devices: M4QD flash hider (included), M4QD MAMS, Triple Tap compensator

• Thread Pattern: 1/2×28 (flash hider)

• Finish: Black

• Length: 6.5 in

• Weight: 22 oz

• NSN: 1005-01-437-0324