Bulb Bases
4 indexed entriesPart of Tools & Home Improvement.
Items
E12
E12 (Candelabra Edison Screw) is a small Edison screw base with a 12mm thread diameter, standardized under IEC 60061-1. It runs at 120V AC in North America and is used for candelabra bulbs, night-lights, and decorative chandelier fixtures rather than general room lighting.
E14
E14 (Small Edison Screw, or SES) has a 14mm thread diameter -- the European and UK counterpart to North America's E12 candelabra base. Standardized under IEC 60061-1, it runs at 230V AC and is used for chandeliers, decorative fixtures, and small appliance lamps rather than general room lighting.
E26 vs E27
E26 (26mm diameter) and E27 (27mm diameter) Edison screw bases differ by 1.0mm in thread diameter. While physical cross-threading is often possible, using 120V E26 bulbs on 230V E27 sockets causes immediate overvoltage failure.
GU10
GU10 is a twist-lock (bayonet-style) bulb base with two pins spaced 10mm apart center-to-center -- the '10' in its name. Unlike Edison screw bases, it has no threads: the bulb pushes in and twists to lock. Originally built for MR16-style halogen spotlights, it is now the standard base for LED and CFL spotlight and downlight fixtures.