On light bulbs there is watts and volts, what is "type A"?

Answer 1

How to read bulb shape codes. The letter designations for each incandescent bulb category indicate the industry code for bulb shape. For example a "BR" bulb indicates a "bulged reflector" shape. The number after the shape code indicates the maximum bulb width in 1/8". A "BR30" bulb has a maximum width of 30 x 1/8" or 3.75".

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