Electronic Ballast, Fluorescent, Input Voltage: 120-277V, Instant Start, Centium Series. For use with the following Linear Lamp Types: (1 or 2) F17T8, F25T8, or F32T8 (25, 28, or 32w), FB32T8 (U-Bent) lamps. Or (1) F40T8. (35I = Individual packaging)