The Maxx Air vent covers have multiple advantages! Fresh air rain or shine, leave your vent lid open to circulate air movement without worrying about water getting in when it rains. Forget to close the vent lid when leaving your site? The Maxx Air covers protect the lid from blowing off in transport. The covers are also durable, and help aid in protecting from possible hail damage and later water damage if you’re not around to cover up that damaged or brittle vent.