Renault and Williams today became the latest Formula One teams to take the wraps off their cars ahead of the new season.
Maintaining the low-key format so far adopted in an effort to save money, the two marques conducted an initial early morning photoshoot at the new Algarve Motor Park situated midway between Portimao and Lagos.
Given the new aerodynamic regulations, the theme is clear as their cars sported a wide front wing and high rear wing, designed to aid overtaking and make the sport more entertaining.
Renault, though, have persisted with their shark fin engine cover employed for most of a 2008 season that ended with Fernando Alonso scoring more points in the final six races than any other driver.
The colour scheme is again yellow, orange and white, although is considerably different in design to last year, and with new sponsors Total dominant on the front and rear wings of the R29.
As for Williams, unveiling the FW31, they are currently running an interim dark-blue winter livery as their definitive scheme is not due to be revealed until some time next week.
The one notable difference of the Williams is that the team will be using a flywheel-based KERS, in comparison to all of their rivals whose system is battery operated.
At the start of the four-day test, that began under leaden skies and on a damp circuit, Nelson Piquet took to the track for Renault, with reserve driver Nico Hulkenberg behind the wheel of the Williams.
McLaren and Toyota, who presented their new challengers last week, had Pedro de la Rosa and Kamui Kobayashi putting their car through its paces, whilst Toro Rosso and new driver Sebastien Buemi were also on track.