Ferrari has retained their controversial Halo-mounted mirrors for the Monaco GP, though have made one significant change.

At the Spanish race almost two weeks ago, the Scuderia incorporated the design as part of their upgrade package, following the go-ahead from the FIA that the mirrors could indeed be attached to the cockpit protection device.

However, the inclusion of a secondary element, which Ferrari argued was for structural purposes but was crafted very much for aerodynamic benefit, raised suspicion and duly the governing body made the design illegal and ordered the Italian team to change for this weekend in Monaco.

Their claim was that if the element was solely for the purpose of the integrity of the mirrors, it would have been located lower than it was where the ability to impact the aerodynamics is less and any benefit would have been coincidental. 

Many thought, given the structural difficulties in mounting the mirrors on the Halo sufficiently to cope with the strong airflow, that would be the end of the idea but Ferrari has persevered and will use them again on the streets of Monte Carlo.

The main difference this time is the winglets above the mirrors have been removed per the FIA's request and it is likely that some kind of strengthening of the support has been done.

The location of mirrors has long been a problem for designers who want to try and locate them in an area where the impact on the airflow is minimal.

Previously, we have seen cars with mirrors mounted on the turning vanes which next to the entry of each sidepod, which were banned due to the impact on a driver's vision.

More recently we have seen the shape of the mirrors alter, with Ferrari pioneering a design which sees the air fed through slots in the back of the mirror.  

The big question with their latest innovation is whether the mirror will be stable at high-speed or if it will vibrate, potentially impairing vision, and if this will be Ferrari's final solution or simply a stop-gap to the next stage of development.