McLaren and AlphaTauri have both implemented significant changes to their cars for this weekend's French Grand Prix at Paul Ricard.
While most of the changes are part of the teams' respective development programmes, some of the design and aero modifications are circuit specific.
McLaren, which is locked in a tight battle for fourth in the Constructors' standings with Alpine, is seeking gains through changes to the MCL36's engine cover, floor body and rear corner.
The Woking-based outfit has also addressed a reliability concern with its car's rear wing, adding a modified endplate.
This weekend's projected high temperatures in Southern France have led to the release of "additional cooling emergency options to ensure reliable running of the Power Unit fluids", according to McLaren.
AlphaTauri's wholesale changes on its AT03 include an updated floor body, floor fences, floor edge, diffuser and engine cover, while more camber has been added to the car's diffuser.
Further up the grid, among F1's front-runners, Red Bull have upgraded their floor fences and rear corner, while Ferrari has tweaked the floor on its F1-75, with Mercedes altering the floor edge and front corner of its W13
The floor element was also an area of focus for Alpine, Aston Martin and Williams where Nicholas Latifi has received the full upgrade package previously implemented on teammate Alex Albon's car.
As for Haas, as expected the US outfit has not updated its VF-22 contender.
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