iRobot Roomba genuine accessories create an invisible infrared wall to restrict Roomba or Braava from entering areas like doorways without steps. It also features a "Halo Mode" to create a circular keep-out zone, allowing you to avoid pet water bowls, etc. *Please check the manufacturer's website for compatible models. ● Power: 2 x AA alkaline batteries ● Dimensions: W45 x D45 x H107mm, Weight: 76g *Please purchase only if you understand that this item has been stored at home for a long period.