WILL SHIP AFTER 15 MAY 2026
 
4140 Alloy steel, black nitrided for wear resistance & corrosion resistance. Adds up to four more settings if your original only has two and has four more settings with reduced port sizes for customizing your settings to your ammo or suppressing.
 
Has the original two port sizes (regular and adverse) for a 550 or full length 556 rifle (as well as a few others in their list of models). This range of 6 settings should cover both long barrel and short barrel/pistol variants.
 
Ports are labeled by dot sizes on front of regulator using the spring detent as the “arrow” indicator for what setting you are on.

Port Sizes:
Port 1, 1.6mm
Port 2, 1.3mm
Port 3, 1.2mm
Port 4, 1.1mm
Port 5, 1.0 mm
Port 6, 0.9mm
 
Be aware: 
These regulators are the fourth run, the side of the regulator with the larger ports had a machining issue that doesn’t make the port sizes obvious. An adverse setting “A” stamp has been added on the largest port location and the ports reduce in size around the regulator counter-clockwise.
 
These gas plugs do not fit SIG 553s.