Bulbrite F12T4 30K 12-Watt Linear Fluorescent T4 Bulb, 3000-Kelvin, Mini Bi-Pin Base, 17 1/8-Inch, Warm White 700 lumens,Long Life (10,000 hours) The Pin-to-pin measurement for this bulb is 17 1/8" Mini Bi-Pin base Available in a variety of wattages and color temperatures Fits T4 lamps depending upon length and transformers