EnvisionLED LED-EM-EXT-G-WH LED Emergency Exit Sign Single/Double Sided (Green) White FinishEnvisionLED LED EM EXT G WH LED EM EXT G WH Product Description Now available is the EnVision LED Emergency Exit Sign. Available in a green and red light, with a single sided and double sided version, place these signs on walls or ceilings near exit locations. With a nickel cadmium battery, the charging time for this fixture is 24 hours, with a discharge time or backup time of 90 minutes. Test to make sure everything works correctly with a test switch