The lightbulb screw is the element that connects to the lampholder and transfers the electrical current to the lightbulb.
Choose the socket
What is the nomenclature of the lightbulbs?
The screws are usually classified with letters or numbers, depending on the features or the number of contacts they need ( in some cases more specific). Here you have an example of the nomenclature of a lightbulb with R7 screw.
The main letters to indentify the type of screw are the following:
B or BA
Swan or Bayonet Screw.
Contact pressure of circular tube.
Contact via simple pressure clamps.
Contact via reinforced pressure clamps.
Clamp contact for light bulbs with rear heat emission protection.
Clamp contact for high heat-emitting rear lamps.
Lamp screws for rectilinear lamps with single ferrules.
Straight lamp screws with reinforced terminals.
Screws for rectilinear lamps with male terminals.
All the types of lightbulb screw
Below you can find the main features of the screws that you can find in our online shop.
E type Screw
They are thread and Edison screws. Named in honour of Thomas Alva Edison, inventor of the lightbulb.
This is a 14mm diameter threaded socket used in small candle or spherical bulbs. They are commonly referred to as fine thread. There are many models of bulbs with E14 socket, below you can see the most popular ones:
This is a 27mm diameter threaded socket. It is used in all types of lamps, wall lights and ceiling lights. The E27 bulb is available in various formats, the most common being G45 (small round), A60 (standard size) and globe. Also known as fat thread bulbs, you can find a wide variety of them in the following links:
These bulb sockets with rear heat emission protection are connected by means of two terminals.
The GU10 is a socket with two symmetrical sockets with a diameter of 5 mm and a pitch of 10 mm. Most GU10 bulbs, both halogen and LED, operate at 220V. They are mainly used in recessed spotlights and ceiling lights. They are a good alternative to GU 5.3. A wide variety of GU bulbs are available.
GU5.3 have two pin plugs with a 5.3 mm pitch without termination. Both halogen and LED usually work at 12V DC (although there are also some 220V AC models in LED). If they go to 12V DC you have to use a transformer. To find bulbs with this type of socket, we recommend you take a look at these categories:
These screws make contact by simple pressure clamps.
Two needle-type plugs with a 4 mm pitch, which slide into the lamp. Both halogen and LED usually work at 12V DC (although there are also some 220V AC LED models). Models that operate on 12V DC require a transformer. If you are looking for G4 bulbs you have them below:
They consist of two flat pins with a pitch of 9 mm. With this type of socket both halogen and LED usually work at 220V AC. If you need bulbs with this type of socket, you will find them all in the following link:
They are often used as replacements for older downlights or some models of table lamps. If you are going to replace a G24 fluorescent bulb with an LED bulb, the ballast or transformer must be removed. In the following link you will surely find the one that best suits your needs:
This is a special type of socket for circular flat or reflector bulbs. These bulbs are mostly used in directional downlights for commercial lighting. It should be noted that the old G53 AR111 halogen bulbs normally operated at 12V DC but LED models are available in both 12V DC and 220V AC. If you replace a 12V DC halogen with a 220V AC LED you will need to remove the transformer. If you are still using conventional G53 AR111 bulbs, we recommend you take a look at these products:
Screws with single terminals for rectilinear lamps.
This is a linear socket connected directly to 220VAC, it has a standardised length of 78mm, 118mm, 138mm and 189mm. They are usually used in spotlights and lamps. They operate on 220V AC. You can find our range of R7s bulbs in the following link: