Mercedes has joined Formula 1's latest design trend in the scramble to copy Ferrari's exhaust wing concept, with six teams adding them for the Miami Grand Prix weekend.

Ferrari grabbed attention during pre-season testing in Bahrain when its SF-26 appeared with a unique winglet to the rear of its exhaust tailpipe.

As well as the downforce gains on offer from the structure itself, it also helped make use of the flow of hot exhaust gases to better manipulate airflow exiting the diffuser and direct it up towards the rear wing.

At the time of the wing's appearance, rivals were unsure if they were going to be able to copy the idea at all.

That was because Ferrari had only been able to incorporate it because of choices it had made with its rear crash structure and gearbox design to allow the extra wing to be added within a legality box.

Any competitors that wanted to copy it to the extent Ferrari had would need to revise their entire crash structure and gearbox, a job too big under cost-cap restrictions to justify.

The only team that had been able to pursue the idea was Haas, which takes Ferrari's gearbox - so had the ability to implement its own version from round two of the season, the Chinese GP.

But despite being heavily restricted in terms of how much they could copy it, Ferrari's competitors have found a way to introduce their own concepts in this area despite bodywork - in theory - not being allowed.

This has been achieved by exploiting a freedom in F1's technical regulations surrounding exhaust mounts.

Any limits in terms of designs in this area are allowed under Article C3.9.2. This allows for a single exhaust tailpipe 'support' - without explicitly specifying how limited it must be beyond falling within legality boxes for the exhaust tailpipe and the crash structure and straddling both.

To help compliance with the demands of the rules, some teams have had to change the angle of their tailpipes, as the Alpine example below demonstrates.

The first-time designs that have appeared in Miami have all exploited this same rule but are all subtly different, as can be seen below - while Ferrari has also evolved its design.

Only Aston Martin, Racing Bulls and Audi do not have an exhaust wing at present, although they may have designs in the offing.

Mercedes

The Mercedes design features a concept that looks similar to a mini rear wing.

McLaren

McLaren's design features a small plate element at the bottom of the tailpipe that helps divert airflow up towards the rear wing, with a 'support' wing clearly visible below

Red Bull

Red Bull's plate cover of the tailpipe is bigger than McLaren's and will be used to divert airflow upward.

Williams

Williams's exhaust support wing looks more like a scoop that helps blow exhaust gases upwards.

Alpine

Alpine's exhaust wing features a double element, with the support bodywork extending across the rear crash structure, below a wing that is fed off the tailpipe.

Cadillac

Cadillac's exhaust wing looks like a partial lid that is fitted to the rear end of the exhaust.