iRobot Roomba dual mode virtual wall barrier

Batteries not included - see video for proof that it works! Included one unit. Used condition but still functions! From factory description: - Dual Mode Virtual Wall Barriers gives you greater control over where your robot cleans - Virtual Wall mode keeps your robot in the rooms you want cleaned and out of the ones you don't - Halo mode keeps your robot away from items you want to protect, like your pet's food and water bowls