TopazÕs 18W, 4100K, Compact Fluorescent Quad Tube 2-Pin G24d Base are the next generation replacement for traditional incandescent lamps and are ideal for multiple residential and commercial applications. TopazÕs Compact Fluorescent Lamps are crafted in shapes to suit every need- from mini spiral to globe, candle shape to 3-way. The Topaz line provides long life, is energy efficient, eco-friendly and offers true energy savings over traditional incandescent lamps.