Find out more about EXFOG Antifog System for eyepro in this recorded version of the livestream done by Patrol Base... "This anti-fog unit is lightweight and compact, which is ideal as it needs to be mounted on the back of a helmet or worn with the included headstrap, and any surplus weight would make the unit slump to one side awkwardly. However due to the low weight this isn't an issue and it will sit comfortably all day.