The SylvaniaGCA 120V 250W Bulb is aclear tungsten halogen bulb. It is T 3 shaped with a glass diameter of 0.437 inches, with a G 5.3 Bi-pin base with an overall length of 2.223 inches. It has a Kelvin temerature of 3200 and is rated at 200 life hours. This bulb has a class C gas with a color rendering index (CRI) of 100 using a CC-8 filament, which may be operated in any position. (Sylvania 54428)