This Westinghouse light bulb is a PS40 500w 250v is used mostly for industrial applications and in barns. It is 9.80'' in overall length, 5'' overall diameter. It has a type: E40 (mogul screw base) base. Its life expectancy is 2,000 hours. It is dimmable and it features clear glass. This bulb is new old stock and it comes in its original packaging.