Like road discs, aero road lids are an innovation that seems to be gaining ground. Kask are the latest helmet manufacturer to launch one, the Infinity, which they claim is "the trailblazer for an entirely new helmet category" – that category being fully vented aero lids.

The Infinity has a system of vents that can be opened and closed by the rider whie on the bike. By adjusting the 'mobile aerator' the airflow can be adjusted from fully open (like a standard lid) to fully closed (like an aero lid) or set somewhere in between. Even when it's full closed the Infinity offers ventilation via "two special internal airflow channels that are fed by two frontal openings", which sounds like a similar approach to Giro's Bongo Hat. I mean Air Attack.

Also new on the Infinity is a 'side rib' which disturbs the airflow over the sides of the helmet; Kask claim that this minimises the low pressure area formed at the back of the helmet, and therefore reduces drag.

The helmet weighs a very respectable 270g; no word on price yet although we'd guess it now sits at the top of Kask's range which previously topped out at the £180 Vertigo. We've got our spies out in Corsica at the moment ahead of the Tour's Grand Depart, so we'll see if we can lay our mitts on one.