Williams' changed brake ducts
As a final update on their FW32, Williams have introduced new brake ducts for both the front and rear brakes. The new ducts feature a shield to prevent airflow into the duct to be disturbed by the rotating front wheel. This design feature is far from new and teams like Renault or McLaren have been running it since the beginning of the season.
It is however likely that Williams have now changed the front brake ducts to better work with the new front wing they introduced in Singapore. While the endplate on that wing has become simpler, the stacked element hangs over the endplate for additional downforce. On the inside, an extra small stabiliser element was added as well, while the black flaps closest to the front wing supports are now similar to Renault's solution.
This extra stabiliser on the cascade has been there since Canada.