The Fox ESS KH 10.5kW inverter and CM4300 x 1 and CS4300 x 4 batteries provide 20.7kWh of storage. I am a solar installer and these have only been temporarily rigged up as part of a test at my own house. They are as good as new and will come with all the warranties which you can register in your name. We could also offer an installed price.
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