Nice to know perhaps, the "E" comes from Edison. And the number is the diameter of the bottom of lamp socket. Totally useless information for many people, but well, nice.
On the one hand there is the so-called large fitting, or E27 fitting.
On the other hand, there is the small fitting, or the E14 fitting.
There are also E40 fittings, but they are mainly used industrially.
Sometimes vintage lamps, such as lighting from France, are provided with bayonet fittings.
Our experience is that in other countries, not everyone finds this easy / practical.
Depending on the lamp, we regularly choose to replace the bayonet fitting when checking / repairing the old lamp, so that you can simply turn a normal light bulb into it.
We developed a reducer / adapting piece ourselves, which comes in very handy for this repair.
Lamp Fittings with Screw Thread on the Outside, when do you use it?
Mainly for clamping certain types of lampshades.
You can turn 1 or 2 shade rings on the screw thread of the fitting and then clamp the lampshade in between.
4. Materials of Fittings
We offer plastic fittings, metal fittings (with porcelain interior) and porcelain fittings.
The fittings we sell online all have a piece of internal thread, M10x1 thread (so-called fine thread). And are therefore easy to attach to a pipe or threaded end that has the same thread.
If you have a rod that has M13x1 thread, you can work with a reducing nipple, from M13x1 to M10x1. And yes, we also have them online.