Flow thru troffers provide light in areas where full filter coverage is required. Fixtures have top perimeter flange to retain filter module. (4) F32-T8 lights are included with fixture. Multi-voltage ballast allows connection to 120-277V single phase power. Standard features · F32-T8 lamps - tubes provided with fixtures. · Voltage: 120-277/1/60. · Acrylic eggcrate grille protects and allows airflow.