It's a developer with fixer incorporated it develops faster than it fixes so you get normal negatives.
Originally Posted by TheToadMen
If a monobath is optimised it can give results no different to a normal dev then fix sequence.
Originally Posted by Michael R 1974
The advantage is they aren't temperature dependent (over a reasonable range) and you process to finality. So there's no need for a thermometer or timer/clock.
The big disadvantage is they really do need fine tuning for a specific film or paper and this is why they mainly get used for applied applications, such as this dental monobath. I worked on them for an industrial application and it was suggested we make one available commercially for paper processing.