This EcoFlow Tech 500W RIVER Mobile Power Station (EF 1 Pro) originally $668.85 drops to $599.95 and then again to $499.95 at HSN. You save 25% off the retail price for this portable charging station. Plus, this item ships free. This is the lowest price we could find online by about $100. The EcoFlow Tech 500W RIVER Mobile Power Station can power your phone, tablet, tv or mini fridge with a 412Whr capacity. Sales tax is charged in most states. Deal expires soon.