Expandable capacity - Increase the capacity of DELTA 3 Max Plus and DELTA 3 Ultra Plus with an extra 2048Wh. Compact size - The extra battery&';s overall volume is reduced by approximately 25% compared to the DELTA 2 Max Smart Extra Battery, making it easier to store, carry and stack. Long lifespan with an LFP battery. Easy to use - Plug-and-play without setup. Monitor the charge level and temperature via the EcoFlow App. Up to 5-Year Warranty - Get peace of mind with a 3-year standard warranty and 2 additional years when you register through the EcoFlow App.