This is a Ushio 500 watt BTL bulb. It has a base of P28s medium prefocus which is in Industrial Light and Specialty Lamps. It has a color temperature is 3050k, it has a filament of C-13D, and it has lumens of 11000. This Ushio 500 watt BTL has a maximum overall length of 4.953 inches, a rated life of 500 hours and a shape of T6.
Cross Reference:
Atlas/Thorn HX17
Atlas/Thorn T/17
Bulbrite 762010 BTL
Colortran 176-167
GE 11966 BTL-Q500T6/CL/P
Grainger 6VN47
Osram Sylvania 54685 BTL 120V
Philips 31891-5 BTL 500W 120V
Philips 6800C
Sunlite 70005 BTL
Ushio 1000083 BTL, JCS120V-500WB