What is being installed here?

[Strand]

LINK

Came across this video, showing what looks like a water-based system designed to improve fuel economy (they're claiming a 25% decrease in fuel consumption for one of the 240Ds).

Per the company's website:

The ambient air is sucked into the bubbler to form humid air by passing through water. It goes through the Retrokit Nano Pro catalytic reactor, heated by contact by the exhaust gases. Once treated, this aerosol dopes the combustion being mixed with the intake air, via the diffusor placed between the air filter and the turbo (or intake in case of atmospheric engines).



Anyone here familiar with such systems? Seems like an odd concept.