From EcoFlow
ecoflow river 3 plus smart extra battery (eb600)- expand the capacity of the river 3 plus to up to 858wh.- choose from two extra battery models to fit your needs: eb300 (286wh) or eb600 (572wh).- an additional 140w of usb-c input and output option.- enjoy a wireless pogo pin connection—no cables or screws required.- reduce your load by using the extra battery independently.