Philips C100S54 Alto High Pressure Sodium Lamp 100W E39 Clear USA 287W. These lamps are an excellent choice for businesses and industries looking for reliable, long-lasting lighting solutions. They are designed to meet the highest standards of safety and quality, ensuring that your work environment remains well-lit and secure. Enhance the visibility in your parking lot or warehouse with the dynamic, 8500 Lumen spread of this high pressure sodium HID from Philips Lighting. The universal burn design of this lamp allows it to operate in any position without losing efficiency to ensure your location is safely litMogul (E39) base better tolerates high temperatures for industrial use Compatible for ballasts with the ANSI S54 code Exceptional efficacy of 94 Lumens per watt For use in enclosed fixtures only High Pressure Sodium HID Bulb, ED23-1/2 Bulb Shape, Mogul Screw (E39) Bulb Base Type, High Pressure Sodium, 9, 400 lm, Bulb Operating Position Universal Burning, 100 W, Trade Number C100S54/ALTO, Rated Life 24, 000 hr, Standard Bulb Type, 2, 100 K, 360 Degrees Bulb Beam Angle, 2 15/16 in Bulb Dia., 7 3/4 in Overall Length, Shatter-Resistant No, Bulb Finish Clear, Color Rendering Index 21, Bulb Minimum Starting Temperature -40 Degrees F If buying multiples of these I can adjust the shipping down for you.