The socket is the part that allows connecting the bulb to the socket. There is a wide selection of bushings for different types of bulbs. The nomenclature for each type includes 1 or more letters (type of lampholder), followed by 1 or more numbers (diameter of lampholder).
Example: The bush E27 would correspond to the type of thread E (Edison) of 27mm in diameter.

• E12: Diameter of 12mm, this is a tamYear smaller than the most commonly used standard E27.
• E14: It is the second most common cap, only varies a little of the E27, with a diameter of 14 to 17 mm. It is normally used for bulbs or lamps.
• E27: This is the most common cap. It has a thick cup shape with thread to be able to adapt to the connector. It measures 27mm wide.
• E40: Has a diameter of 40 mm, it is the largest thread of this tIpo.
• G4: With a distance between pins of 4.0 mm. It is a type of cap that is frequently used in appliqués, ceiling lamps and hanging lamps.
• G5.3: With a distance between pins of 5.33 mm. The GU 5.3 socket format is a format widely used in small led floodlights with transformer. Usually used in halogen lamps and dichroic halogens.
• GY6.35: With a distance between pins of 6.35 mm, trOf a model similar to the previous one.
• G9: With a ditancia between pins of 9,0 mm. Usually used for ceiling lamps and hanging lamps.
• G13: With a distance between pins of 12,7 mm. It is used in fluorescent tubes.
• GX53: With distance between pins of 53 mm. Its most common use is the installation in light bulbs to illuminate furniture or unusual places. It does not need transformer.
• GU10: With a distance between10 mm pins. The GU10 bushing shape is a widely used format in small transformerless LED spotlights. Usually used in dichroic halogen lamps.
• B22: Type of bayonet connector used in countries such as Africa, India and Ireland.
• MR16: Its use is normally limited to 12V halogen lamps.

hen we talk about IP code (International Protection) we talk about an international standard (IEC 60529) which classifies the protection against external factors, solid or liquid, that has a component or electronic device; LED strips, controllers, meters, security cameras, etc.

This alpha-numerically standard has been designed to sort different levels of protection. Nomenclature starts with IP followed by two numeric values.

- Example IP68:

The first value ranges from 0 to 6 and indicates the protection against solid agents. In this case, strong protection against dust.

The second value is between 0 and 8 and indicates the protection against liquid agents. In this case the complete and prolonged immersion during the time specified by the manufacturer.

We could say that the larger the number is greater IP protection has a device.

In below table, we can see different IP protections levels available.

IPXX	First digit (IPxx)	Second digit (IPxx)
0	Unprotected.	Unprotected.
1	Protection against objects of> 50 mm diameter.	Protection against vertically dripping water.
2	Protection against objects of> 12.5 mm diameter.	Protection against inclined drip water up to 15°.
3	Protection against objects of> 2 mm in diameter.	Protection against water projected from any direction, up to 60°.
4	Protection against objects of> 1 mm in diameter.	Protection against splashing water any direction.
5	Ingress of dust is not entirely revented, but it must not enter in sufficient quantity to interfere with the satisfactory operation of the equipment .	Protection against water jets.
6	Dust tight.	Protection against strong jets of water.
7		Protection against complete immersion up to 1 meter for 30 minutes.
8		Protection against complete and prolonged immersion.

Although it seems very complicated nomenclature IP standards is only a division in double digits, where each digit indicates that it is being served to meet these regulations. For the first digit would be: 5 ingress of dust can not be avoided, but it must not enter an amount that interferes with the proper functioning of equipment. For the second digit 4 is placed theequipment in your usual workplace. You should not enter the water thrown from any angle to an average of 10 liters per minute and a pressure of 80-100kN/m for a time not less than five minutes.