It’s amazing how much of a difference just keeping the wind off your feet will make to your temperature.
Primarily designed as an aerodynamic aid, the Nano is made of wind and waterproof fabric, with fully taped seams, so while it offers no thermal attributes to speak of, it’ll still keep your feet comfy, which makes it suitable for temperatures of 8°C and up.
The silicone-treated upper has a certain amount of stretch for a close aerodynamic fit, although Castelli reckon it’s not so suited to bulky MTB shoes. The underside is rubberised for more durable walking and the covers come in five sizes to aid fit.
Superb aerodynamic properties with added protection from the elements.