A new rear wing was tested at Barcelona on February , with four horizontal endplate slits (No1) instead of three and triple flap separators instead of two (No2 arrow shows the central one while the two others are at the sides of the endplates). The central separator now has no role on moving the second flap like happened before .
The second flap , which is now smaller , has a boxy part close to the endplates (No3) which I suspect to house part of the flap angle adjuster mechanism and also to play role on moving the flap .
W02 movable rear wing looks simple but effective at the same time . The team exploits the two flap separators ( No1 ) to adjust the attack angle of the second flap enjoying a low drag configuration .The separators push the flap upwards , a motion helped by a rotation axis marked with No2 arrows . Housing the flap adjuster inside the endplates with the help of the flap separators to reduce the attack angle and also making the main plane rigid enough made the mechanics to abolish any need of a wing centre pillar .