Lamp, Shatter-Resistant, CFL, CFL 4W/MINI UVB TWIST/27K (PK X 1, 4 Watts, 120 Volts, 250 Initial Lumens, 2700 K, 82 CRI, Electronic Ballast, Instant Start Type, Spring Shape, 1.2 IN Dia, 3.5 IN Long, Twist Bulb, Medium (E26) Base, 8000 Avg Life Hrs, Silicone Coating