Universal Voltage 90 Mins Duration: Supporting 120-277V universal voltage, compatible with both commercial and residential use. Equipped with NiCd backup batteries that provide over 90 minutes of illumination during power outages. Two adjustable LED light heads allow the led exit lights to be pointed in any direction needed. Superior Quality: Constructed with injection-molded thermoplastic housing certified to UL94V-0 flame retardant standard. A high-density material provides exceptional heat resistance and impact resistance, thus maintaining reliable operation in harsh environments. Versatile Mounting: Our emergency exit light offers two installation options, ceiling mount wall back mount. All mounting equipment are included in the package. Multiple Application: Our double-sided exit sign is compliant with emergency egress requirements for various environments, including offices, hospital, stairwells, hallways, exit doors, restaurants, and warehouses. Safety Operation: The LED exit sign is HARDWIRED. Before pressing the "TEST" button, please check that the battery connection port (black and red wire) is connected properly.