Air cooled lights are ideal for those looking to get their room/tent temperatures down. The lamps inside grow lights burn very hot and raise the whole temperatures of the room, this can have a negative impact or in extreme cases even scorch your crop. This tends be more prominent in the summer months.
Having air cooled lights allows you to blow cooler air through the shade and around the lamp, this cools the lamp and keeps the temperatures in room down. It is important to note when you are fitting your air cooled lights that you ensure, the fan you are using to cool the lights is facing the right direction, you want the fan to blow air through and around the lamps not extract the hotter air from around them. this is a common error, extracting the hotter air from around the lamps will not be as efficient at bringing the heat down.