Formula 1 teams will face close scrutiny of their suspension systems this season to ensure they are not using them to influence ride height.
In this latest video from Motorsport.tv programme The Flying Lap, Craig Scarborough explains why the rules clarification is necessary.
"We had last year a suspension regulation change over the winter, which was driven by teams querying the legality of certain aspects of suspension," says Scarborough. "That's happened again this year.
"It's driven by some teams, probably to give someone an advantage, or to give someone a disadvantage."
Scarborough explains how the suspension systems can achieve this and discusses what impact this might have on the 2018 season.
He also explains how the FIA will ensure cars comply with this.
We'll have to wait for 2019, but the latest F1 driver weight ruling should mean that the lighter drivers no longer have an advantage - or that drivers will need to go on crash diets.
Here, Scarborough explains the impact of the mooted 2019 F1 driver weight regulations.