TYT and Retevis radios come off the same production line. They are sold with the same hardware and casings, the firmware, CPS and code plugs are inter-changeable – just a different badge and model number.
They have 2 mono bands, TYT MD380 / Retevis RT3 and TYT MD390 / Retevis RT8.
Then came the dual bands handhelds. TYT launched the MD-2017 then came the Retevis RT82 (also sold under the Moonraker badge as the HT-500D).
Following that, the dual band mobile was launched with TYT staring with the MD-9600 followed by the Retevis RT90.
And to add further confusion, Retevis launched the Ailunce HD1 dual band handheld.
Then TYT/Retevis decided to launch the MD-UV380, MD-UV390 & RT3S dual bands which are a mix of the mono and dual band radios.
The sub menu’s cover each of the radios – in order of launch.
Links to the CPS/Firmware
Retevis / Ailunce – http://www.retevis.com/resources-center