The SOF 556K QD is a compact 5.56mm rifle suppressor made in Inconel 718 with 3D metallurgical additive manufacturing. It measures 5.20 inches long, has a 1.60-inch diameter and weighs 15 ounces, which suits builds where overall suppressor length matters. SOF lists it with an unrestricted minimum barrel length and a maximum velocity of 3,300 FPS. A NANO G coating is intended for high-temperature use. The quick-detach mount makes it a good match for a rifle that moves between suppressed and unsuppressed use.

Key Specifications

• The caliber is 5.56mm, the standard cartridge for AR-15 and M4-pattern rifles.
• Overall length is 5.20 inches, slightly shorter than the standard SOF 556.
• The material is Inconel 718, 3D printed with metallurgical additive manufacturing.
• The mount is a 1×16 LH quick-detach (QD) system with an AI Nano muzzle device.
• It is full-auto rated with an unrestricted minimum barrel length, and SOF lists durability at three 30-round magazines to the heat threshold at a one-second cadence.

Frequently Asked Questions

Is the SOF 556K QD quick-detach? Yes. It uses a quick-detach mount with a 1×16 LH interface and an AI Nano muzzle device.

Do I need ATF approval to buy this? No. As of October 9, 2026, ATF no longer requires Form 4 approval, registration or a tax stamp for suppressors. It transfers on a Form 4473 with a background check through a Class 3 (SOT) dealer. State and local laws still apply.

Buy the SOF 556K QD Suppressor, 5.56mm, Quick-Detach 1×16 LH

As of October 9, 2026, this suppressor transfers on a Form 4473 with a background check at your Class 3 (SOT) dealer, with no Form 4 or tax stamp; state and local laws still apply. Order through SOF’s suppressors lineup and our Lubbock, Texas team will handle the transfer and it ships fast to your Class 3 dealer. If you want the shorter body and tool-free removal, the 556K QD is the version to order.