Linear Fluorescent Bulb, Bulb Base Type Medium Bi-Pin (G13), Bulb Shape T12, Color Rendering Index 90, Color Temperature 6500K, Lumens 1,687 lm, Light Technology Fluorescent, Nominal Length 4 ft, Shatter-Resistant Yes, Watts 40 W, Voltage Ballast Dependent, Standards Meets 2012 Lighting Legislation Energy Standards, ANSI Code 1010-1, Bulb Minimum Starting Temperature 50 Degrees F, Bulb Start Type Rapid, High Output No, Overall Length 47 3/4 in, Rated Life 20,000 hr