(Pack of 6) F54T5/865/HO 54-Watt T5 High Output 6500K Daylight Bulbs Base: Miniature Bi-Pin (G5) Can be used for Growing and Home/Office usage Lifetime: 20,000 hours Fits 4 foot fixture (actual size including prongs 45.2") Color Temperature: 6,500K (grow) Daylight Designed to deliver performance with 4,800 High Lumen output and Full Spectrum