Flair has twice the battery capacity of all known competitors. With normal usage, fresh C batteries (two) in a Smart Vent will last about two years. When your batteries start to run low, you will automatically receive an email.
If you'd rather not use batteries, Smart Vents can be wired. Flair is the only Smart Vent that offers a powered option!
Important: If wiring Smart Vents, do not use batteries.