Philips (248146) H37KC-250DX 

Mercury Vapor Light Bulb

 General Characteristics - 
Base Mogul [Mogul]
Bulb ED-28 [ED 90mm]
Bulb Material - Hard Glass
Bulb Finish - Coated
Operating Position - Universal [Any or Universal (U)]
Life to 5% failures 5000 hr
Life to 20% failures 10000 hr
RatedAvgLife(See
Family Notes)
15000 hr