Expand your energy storage with the Fortress Power DuraRack. This iron enclosure stores up to 4 eFlex 5.4kWh batteries, and is expandable up to 4 units (15 eFlex batteries, 81KWh). The DuraRack includes integrated busbars and a DIN rail heater mount. This enclosure can be free-standing or pad mounted and is safe for indoor and outdoor installations. BATTERY MODULES NOT INCLUDED