The Iota ISD-420-EM-A self-diagnostic emergency backup battery provides emergency operation for 90 minutes and utilizes AC output for compatibility with low-mercury content amalgam lamps. This emergency ballast will self-test for thirty seconds every month annually and will diagnose potential problems within the light fixture. It is compatible with most 13- to 57-watt 4-pin rapid start compacts including twin tube, triple tube, quad, 2D and straight. UL listed for damp locations, this backup battery operates at 120-277 volts, features a test switch, charge indicator kit, and internal self-diagnostic circuitry. The Iota ISD-420-EM-A emergency backup ballast comes with a 5-year warranty. This ballast is not to be used with retrofit LED tubes.