In Bahrain, the F138 received more improvements to the car's aero package.
The aero package is almost entirely copied from the Boss 302R race car.
On certain stages, the aero package alone will be worth about a second.
Williams's new aero package was not working as they would like as Rosberg qualified P10.
They were mighty through this sector last year and their aero package is still the strongest on the grid.
While basically the same dimensions as its predecessors, the aero package has been completely redone with a dramatic improvement in down force for a small drag penalty.
The body and aero parts will not be in effect until 2013, so for 2012 all teams used the identical aero package provided by Dallara.
With a new longer wheelbase to aid stability and a totally new aero package that had hoped to give the car great potential.
The rear bumper features a diffuser built into the bumper and completing the aero package with a huge rear wing.
The full aero package earned the racing CSLs the nickname "Batmobile".