You can expand the power from 1800W to 3600W by connecting to another Nature's Generator Lithium 1800 by the Nature’s Generator Lithium 1800 Combiner. Rated Power 1800W 1800W 3600W 3600W 3600W. Connect the red connector of Nature’s Generator Lithium 1800 Combiner to the red connector of Nature’s Generator Lithium 1800, Connect the black connector of Nature’s Generator Lithium1800 Combiner to the black connector of Nature’s Generator Lithium 1800 and connect the green ground connector of Nature’s Generator Lithium 1800 Combiner to the copper connector of Nature’s Generator Lithium 1800.
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