[Fast Green Charging] Charge DELTA 2 Max wherever there's sun with portable solar panels. With a single 400W panel that has a high conversion efficiency of up to 23%, top-up in 5.1 hours. Add another 400W panel and charge in as fast as only 2.6 hours. Ideal for power outages at home or outdoor. [0-80% in 43 Mins] DELTA 2 Max utilizes EcoFlow's dual charging technology, and with a combined solar and AC input of 2400W, 80% charge in only 43 min. Or stick with AC for an 80% charge in a speedy 1.1 hour. [Upgraded LFP Battery Offers More Than 10 Years of Use] LiFePO4 battery chemistry provides 3000 100% charging cycles till it lowers to 80% capacity. That's 6× more cycles than the industry average and more cost-efficient. DELTA 2 Max also comes with an extended 5-year service.