Some time ago I posted a handheld device that could defog goggles when placed on the forehead. While effective, it requires the player to have a free hand and may be awkward to use in the middle of the action. Therefore I designed a new version that can be attached to a very common model of goggles.
The 3D printed part is inserted in the curved airflow gap above the eyes. The small inserts may break due to their small layer surface, so I added holes for reinforcement screws. A ziptie as shown above is also useful for a reliable attachment.