Only fog elimination system compatible with 509 brand goggles
Custom top mounting plate fits all 509 Sinister and Aviator goggles and most other brands of goggles
Three different settings; On, Off, and Automatic
Automatic setting senses the humidity level of the goggle and activates a tiny fan before you start to fog. The sensor will keep the fan on until warm moist air is removed and then the fan will automatically shut off