I recently got a couple of very basic Zastone ZT-X6 2W UHF handheld radios. The actual brand seems to be WLN and the model KD-C1 (because the programming software I downloaded from Zastone is named after this WLN model? I know they have a number of different brand names for this one product).
Looking in that KD-C1 programming software, and Chirp as well, there's an option for this device called "Embedded Message" (in Chirp, it's under the Settings-tab on the left for this radio).
I am not familiar with this functionality and I've tried some googling, but thought this would be a better place to ask: what is the meaning of this "Embedded Message"?