The diameter of the Brigade Manufacturing AR 9mm 9 inch w/ Mini Can Complete Upper Receiver handguard is 1.35".
The Brigade Manufacturing AR 9mm 9-inch w/ Mini Can Complete Upper Receiver does not include a BCG or charging handle. These uppers are LRBHO compatible.
The Brigade Manufacturing AR 9mm 9 inch w/ Mini Can Complete Upper Receiver can be used with either buffer tube. However, you will need a 9mm buffer and spring or a heavy buffer and spring. I recommend using the buffer assembly or one similar at the link below.
https://www.opticsplanet.com/angstadt-arms-ar-15-9mm-5-4-oz-carbine-buffer-assembly-w-carbine-buffer-spring-9.html
The Brigade Manufacturing AR 9mm 9 inch w/ Mini Can Complete Upper Receiver is compatible with Glock magazines. So it might work with CMMG 9mm magazines but I recommend contacting the manufacturer to confirm.
The Brigade Manufacturing AR 9mm 9 inch w/ Mini Can Complete Upper Receiver will work with most AR9 BCG's. The BCG at the link below will work.
https://www.opticsplanet.com/brigade-manufacturing-9mm-ar-lower-parts-kit-w-grip.html
The Brigade Manufacturing AR 9mm 9 inch w/ Mini Can Complete Upper Receiver does not come with a BCG or Charging Handle.
The Brigade Manufacturing AR 9mm 9 inch w/ Mini Can Complete Upper Receiver is offered in 4 different colors. Black, FDE Midnight Bronze, and Tungsten. You will receive the specified color that you choose.