Neon sign powered by 12v DC power transformer by default. It's plug-in to work. 2. We can make it work with 5v USB power bank for small sign or 12v power bank (battery) for large sign 3. The power bank(battery) is NOT included in the order. We can guide you to buy from Amazon.  4. 12v Power Bank Amazon Link:   https://amzn.to/3R6Drbn