Virtual Wall Lighthouse uses an invisible infrared signal to guide Roomba through room-to-room cleaning. Contains Roomba in one room until the room is completely vacuumed then directs Roomba to clean the next room. Also blocks off-limit areas in your home.Standard Features:Use in Lighthouse Mode to contain Roomba in one room until the room is completely vacuumed before Roomba moves on to the next roomUse in Virtual Wall Mode to block off-limit areas in your homeOnly compatible with select Roomba 500 Series models, Roomba 780 and 790 and Roomba 877 and 880. Compatible 500 Series Robots include: 571(01), 571(02), 572, and 573.|Specifications:Package Dimensions: 3" x 4.5" x 4.5"Package Weight: .4 lb.What's In The Box: 1 Virtual Wall Lighthouse (Requires 2 C Batteries, Not Included)The iRobot limited warranty shall not apply to failures or problems which are caused by products or equipment not authorized by iRobot Corporation.