Here is a complete set of 4 light up musical Caroling Cottages from Hallmark, 2009. I got these new and removed batteries every time before storing. These work perfectly. Each house needs 3 AAA batteries, not included. They are not synced wirelessly. Each house has cord and female end. Plug house into each other to sync lights and music. Each house plays 2 different songs and light shows. Please feel free to ask questions. No flaws, all work great!