CMMG MK4 Receiver Extension Castle Nut – Black

The CMMG MK4 Receiver Extension Castle Nut in black matte is a must-have for AR enthusiasts. This durable component ensures a secure fit for your AR buffer system, boasting a precise design with a 3.9-inch length. Crafted by the trusted CMMG brand, this part is ideal for those looking to upgrade or maintain their AR rifles. Lightweight and easy to install, it offers reliable performance in demanding applications. Elevate your AR build with the quality craftsmanship of CMMG.