Oval Gear Spanner Element Belt

Hello, I was wondering if anyone has a technical explanation for the "oval gear-sprocket chain"? I have read that this is a "Contitech" development and in the
Newer pump-nozzle engines are now available for use. Here, one writes that these belts {BELT_TYPE}
should be able to last up to 250,000 Km.
The function of the oval gear span element is still unclear to me, and I haven't found much information about it.
Can anyone help, maybe even a link?

Thank you!

Here's something to read.