G13 bipin/single pin/recessed double contact From the 1930s, more common format since the 1980s. T9 T29 1 1 ⁄ 8 28.6 G10q quadpin contact Circular (circline) fluorescent tubes only T10 1 1 ⁄ 4 31.75 G13 bipin T12 T38 1 1 ⁄ 2 38.1 G13 bipin/single pin/recessed double contact Also from the 1930s, not as efficient as new lamps. T17The suffix after the G indicates the pin spread; the G dates to the use of Glass for the original bulbs. GU usually also indicates that the lamp provides a mechanism for physical support by the luminaire in some cases, each pin has a short section of larger diameter at the end (sometimes described as a peg rather than a pin); the socket allows the bulb to lock into place by twisting it ...
Download Image: download
