F21T5 - 21 Watt - T5 - High Efficiency - Fluorescent

If you're looking for 21-watt T5 fluorescent lighting, you've come to the right place. F21T5 bulbs provide a whiter, more natural light than other fixtures and work well in residential and commercial applications. The T classification means the bulb is tubular in shape, with flat sides and a rounded top. The number following the T represents the dimension of the lamp in eighths of an inch. That means an F21T5 bulb is a 21-watt fluorescent tubular lamp with a diameter of 5/8". These bulbs are highly efficient and have life spans between 20,000 and 36,000 hours. When you need 21-watt T5 fluorescent lighting, 1000Bulbs is your go-to online lighting retailer.