Originally only available as a 'DIY' project, several manufacturers now produce the MULTI-module.
Modules are available to fit in the standard 'JR' style module bay found on most radio systems, or 'Lite' modules available for the smaller module bay of 'Lite' radios.
Some radios are available with internal MULTI-module boards. Internal modules work in exactly the same was as external modules.
All currently-available MULTI-Modules are based on an STM32 micro-processor.
Vantac MPM Lite, URUAV TMX5, and URUAV TMX5 Lite modules are not supported by the MULTI-Module project. These modules have been found to be be using the incorrect MCU (processor), which does not have the correct amount of flash memory.
If you have one of these modules you should contact the vendor or manufacturer for support and firmware updates.