All in One ESS is a full hybrid battery and inverter solution. What's more, it has expandable modules to grow as your needs do. It can fit onto an existing Solar system or as part of a new install. It is designed to become an integral part of your home energy solution. There are two kinds of All in One ESS for customers to choose from, including All in One ESS 5KW Inverter Battery System and All in One ESS 8KW Inverter Battery System. http://www.youthpowergy.com/all-in-one-ess/