Kodak Kodaslide 1 and 2 stereo viewers. Graflex Stereo Graphic viewers. TDC Stereo-Vivid stereo viewers. TDC stereo viewers (older models). Throughout the 1960s and 1970s, these were the standard bulb that fit most all viewers that had 2 - 1.5 Volt batteries: size AA, C or D.
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