(10 Pack) F34T12 / CW / RS / EW / ALTO - 34 Watt - T12 - Cool White 4100K - Replaces 40-Watt Linear Fluorescent Light Bulbs (Pack of 10) F40CW/SS/ECO Color/Finish: Cool White 4100K Average Lifetime: 20000 hours Medium Bi-Pin (G13) Base Extra Long Life, Rapid Start