40W Double T6 Circline Lamp * Light Output (40w): 2 800 lumens * Light Output (58w): 3 700 lumens * Color Temperature: 2 850 degrees Kelvin * Color Rendering: 84 CRI * Minimum Start Temperature: -20 degrees Fahrenheit * Maximum Operating Temperature: 160 degrees * Fahrenheit Rated Lamp Life: 10 000 hours * Dimension (40w): 7.5" diameter 0.75" thick * Dimension (58w): 9.0" diameter 0.75" thick * Certifications: UL CUL * Manufacturer Warranty: 1 Year * Origin: China