BRT

These are 9mm RDB A1 style uppers which are compatible with the CMMG RDB BCG's and are integrally suppressed ready. They have the same barrel profile as our straight blowbacks, except for the barrel extension and feature M18x1 threads and porting like the MP5SD. The ports bleed off gas so that 115 grain ammo will be subsonic. These uppers are compatible with MP5SD type suppressors only and we highly recommend HiTec Arms as they're excellent quality and easily serviceable. Please visit them at https://hitecarms.com/ These work perfectly with our SD uppers. Our handguard is designed specifically to mount the MP5SD shroud onto and is now included. The Radial Delayed Blowback system operates with a standard carbine buffer and doesn't require the heavy buffers that are usually needed for reliable cycling. The barrel porting combined with the RDB system makes these soft shooters with very little recoil. Please allow 2 weeks for delivery..