https://laseredgetactical.com/shop/ols/products/angstadt-arms-54-oz-9mm-buffer-kit-w-spring-and-spacer

The Angstadt Arms 9mm heavy buffer assembly kit is compatible with blowback AR-9 style firearms chambered in 9mm, 40S&W and 45ACP. Includes 8oz solid state buffer and carbine buffer spring. Manufacturer Part #: AA45BUFKIT

Complete 8oz 9mm AR-15 buffer kit gives you everything you need to get your 9mm or 45acp AR-15 running smoothly. It is compatible with both GLOCK® and Colt® style magazines.

Contents include:

• 8oz 9mm AR-15 carbine buffer assembly. The buffer body is extended in length, there is no need for a spacer
• Carbine buffer spring