Bulb base reference
Find dimensions, interchangeability rules, and compatibility guides for screw, pin, and bayonet light bulb bases.
Bases
E26, E27, E12, E14, GU10, G9, GU24, MR16, G4, B22 — specs, voltages, and fixture guidance.
Shapes
A19, A21, BR30, PAR38, MR16, G25, T8 — bulb envelope shapes and size codes.