Most recent
ANSI C78.1407-2004 (S2020)
Electric Lamps - Condenser-Reflector, Four-Pin Prefocus-Base Projection Lamps - Dimensions
This standard specifies the dimensions essential to the interchangeability of condenser-reflector lamps having four-pin prefocused bases, T12 or T14 bulbs, and used in 8mm motion-picture projectors. It is not the intent of this standard to prescribe operating characteristics or details of design.
NEMA: National Electrical Manufacturers Association [nema]