Force India F1 have followed Ferrari and McLaren in adding an extension to the wheels to help brake cooling and control the wake behind the front wheel. Since teams started adding static wheel fairings at the fronts and dynamic carbon fibre items glued inside the rim, the FIA put down some regulations that limit freedom, but nonetheless still allow some creative benefits. The additions must now be a rigid part of the rims and be made of AZ70 or AZ80 magnesium alloy, just like the rims themselves.
The benefit of these additions comes from controlling the wake behind the front wheels. While they can improve efficiency of the brake cooling, teams are most interested in cleanly releasing the air that went through the rim. Improving this can easily gain several points of downforce generated by the floor and diffuser.
This effect also partly explains why teams are currently less interested in applying such solution on the rear wheels. All three teams mentioned are running conventional rear wheel rims.