The scoop was first seen on Red Bull's RB13 in 2017, and appeared to be an attempt to satisfy the FIA's regulations for the front crash structure while trying to stave off any high pressure areas produced behind it as airflow begins to detach.
Having used the scoop since then, Red Bull has now arrived at Monte Carlo with a regular 'thumb-tip' design - much like the one used back in 2016.
Red Bull fins
The new fins (red arrow) augment this effect, and the bottom half directs air through the slot in the floor next to them.
However, the tips incline in a different direction, working with the curved top side of the floor to bring the airflow on top of the car around the midriff of the sidepods.
Those together aim to limit the impact of the rear tyres, which kick up a large supply of turbulent air and can ultimately damage the effectiveness of downforce-producing elements at the back of the car - namely, the diffuser and associated components.