Headlight Help
There has to be an opening for moisture to fluctuate to match outside ambient ait temp and dew point. This can also be used as a drain hole. If the housing is totally sealed, it will have the atmosphere and humidity level of that you sealed it at. So if you sealed on a humid morning, by noon time it will be cloudy and some water collecting at the bottom.
Ideally, the hole is at the bottom so it can also act as a drain hole for excess moisture. To prevent water from entering, they are usually covered with a cloth/fabric sticker, that way water sitting on the inside will slowly seep out (and can temp/humidity) but water that is splashed on it from the outside wont go in.
Ideally, the hole is at the bottom so it can also act as a drain hole for excess moisture. To prevent water from entering, they are usually covered with a cloth/fabric sticker, that way water sitting on the inside will slowly seep out (and can temp/humidity) but water that is splashed on it from the outside wont go in.