GE Industrial Solutions ProLine Electronic Ballast, 120, 277 V, 50/60 Hz Operating Frequency, 1 W Wattage, Parallel Circuit, 1 Lamps, Instant Start, Ballast Factor: 0.87 to 0.98, 70 deg C Operating, Dimensions: 9.5 in L x 1.3 in W x 1.18 in HHigh-performance electronic ballast for all general fluorescent applicationsInstant start electronic ballast for long lamp starting cycles and low initial costMulti-voltage technology handles voltage from 120 to 277 VLightweight, low-profile housingParallel lamp operation means system maintenance is easier to manage