In its own series of "updates at every race", McLaren have revised the sidepod panel. Attached to the car's floor and to the sidepod itself, all connections also fulfil an aerodynamic purpose. The panel itself is now more curvy at the bottom, while the section where it is closest to the sidepod now has a leading edge leaning inwards, aiming to direct more air around the outside of the panel.
The panel, although apparently simple, is extremely important for the car's rear end efficiency. It attempts to overcome the turbulence behind the front wheels and guide air smoothly along the sidepod. Eventually it influences the diffuser, rear wheel drag and the rear wing.