I don't know what that is. Sounds like a driver safety concept.
I read today that the “shark fin” and “T-wings” behind the driver's head will be outlawed for next season.
Since the fin and T-wings add downforce, I don't understand why they have (or will be) banned.
I did a search and found what the Halo device looks like. It starts with a center post swept back starting in front of the cockpit and sweeping back and up to just forward of the driver. Then the structure splits to two arcs on either side of the driver compartment that sweep back and then downward to connect to the car body on both sides of rear of the driver compartment. Looks like it would protect from cockpit intrusions from other cars, but will make it much more difficult to exit the car.