Lazer's seemingly innocuous Aero Shell add-on is one of those rare products that provides more value than it costs, in this case by effectively turning your airy summer helmet into one more suited for cold-weather duty for just US$20.
The snap-on polycarbonate shell is easy to pop on or off – with no tools or fasteners – and seals off all of the upper vents from cold wind and biting rain. Adding the Aero Shell by itself extended the comfort range of our Helium test helmet down below 10°C (50°F) on the road and even further still on mountain bike rides where there isn't as much wind to worry about – and that's with a shaved head, no less.
Adding a thin earband took that figure down closer to the freezing mark by sealing up the lower edge of the helmet while a standard winter cycling cap makes the combination suitable for truly nasty conditions.
That protection comes at a cost of less than 50g of weight while a cutout still allows access to Lazer's Rollsys fit adjustment dial – plus the thin material adds virtually zero bulk and won't affect how your helmet fits on your head, either. Things won't get clammy, though, as the rearmost vents are still left open to exhaust hot air and sweat vapor.
The clear colour option is even nearly invisible once installed but Lazer also offers brighter and bolder Ronde van Vlaanderen and Paris-Roubaix-themed versions if that's more to your liking.
The Aero Shell's only major drawback is that it's impossible to store if it warms up significantly during your ride – unless you've got a follow vehicle, that is. While light and thin, the semi-rigid material simply doesn't collapse at all for tucking into a jersey pocket, so if you leave the door with it attached, plan on coming back with it that way, too. In addition, it's currently available only for Lazer's Genesis and Helium models.
Especially cost-conscious buyers might point out that while not a huge amount of money, US$20 is still a fair amount to pay for what is essentially a single bit of moulded plastic and in that sense, it's hard to argue. But considering what that money gets you in return, we still contend the Aero Shell is a no-brainer for riders that have to tackle cooler conditions and already have a compatible lid. In fact, we're so smitten with the concept that we wish every helmet manufacturer would follow suit.