The modern lighting industry has been developed dramatically since the first lighting bulb’s invention. Technicians and designers in the lighting industry create more and more lighting products in the market. As a very important light source, Led lighting bulbs are popular always in home lighting or even commercial lighting. For common consumers, it’s very confusing to know and select a suitable Led lighting bulb from various shapes and sizes. For example, A19, G45 or C37 bulbs or such model numbers designed on the package. What’s the definition of these model numbers? As a Led bulbs manufacturer in China, Quark lighting would like to share some useful information concerning LED lighting bulbs shapes and bases.

  1. Led Light bulbs base

We begin with the Led lighting bulbs bases or sockets(some people call sockets also). Led Lighting bulbs bases usually come in a letter-number format. For example E14, E26 etc. The letter E means the shape or form of base(Edison screw in), the numbers 26 which is usually in millimeters represent either the width of the base or the distance between the pins. E26 is a standard USA screw-in bulb base. But if you see the E27 base designed in the package, you should know E27 bulbs will fit E26 sockets because E27 is the European standard screw-in bulb base.

popular led lighting bulb base

Normally Led lights bulbs use the same bases and sockets as traditional light bulbs. We select some popular lighting bulbs base and sockets in the market for explanation.

NameDesignationPopular modelTypical applicationsCountry
BBayonet Collar BaseB15BulbsGreat Britain, Australia or other British Commonwealth countries
EEdison Screw Light BaseE5BulbsWorldwide
E12Candelabra bulbsUSA, CANADA,JAPAN etc
E40High power bulbs/Corn bulbsUSA, CANADA, JAPAN,EUROPE Etc
GMultiple Pin Type Light Bulb BaseG4MR11 and other small spot lightWorldwide
G5T4 or T5 tubesWorldwide
Gu5.3MR16 and other small spotlight bulbWorldwide
GU10MR16 and other small spotlight bulbWorldwide
G13T8 or T10 tubesWorldwide
  1. Materials of Led lighting bulbs base

Led light bulbs bases are manufactured to the same standards as traditional lighting bulbs. Normally Led lighting bulbs bases are made of alloy and metal such as iron, copper, alum, nickel-plated iron, nickel-plated copper, galvanized copper, galvanized iron etc. Different materials lead to different quality of bulbs. A qualified Led lighting bulbs base should be bright, long-lasting and rust-proof. Cheap and poor quality materials cannot be used to produce a high-quality lighting bulb base. Quark lighting selects always high-quality base made of nickel-plated copper or nickel-plated aluminum etc.

IronCheapestCommon material, but high risk of rust
Galvanized ironCommonCommon material, some risks of rust
AlumHighBright and no risk of rust
copperHighBrassy color and no risk of rust
Nickel-plated copperHighBright, long-lasting and no risk of rust
nickel-plated alumHighBright, long-lasting and no risk of rust
  1. Led lighting bulb shapes

Led Light bulbs come in various different shapes and sizes. People can get confused to distinguish and select all these model numbers such as A19,G45,ST18, C35 ETC. Quark lighting supplies most types of LED lighting bulbs in high quality and reasonable price. There are eight common lighting bulbs shapes in the market:

  • Arbitrary (A)
  • Bulged Reflector (BR)
  • Candle (C)
  • Globe (G)
  • Multifaceted Reflector Lamp (MR)
  • Parabolic Aluminized Reflector (PAR)
  • Blown Reflector (R)
  • Tubular, Straight tubular (T,ST ETC)

Different shapes help the Led lighting bulbs to create a special lighting sphere and beam angle. So some special lighting applications need specific bulbs shapes. Designers in the lighting industry bring more and more ideas about the Led lighting bulbs shapes. Maybe the graphic below will give you some more ideas about the LED lighting bulbs shapes.

After introducing the shapes of lighting bulbs, we come to the sizes of different shapes. Every shape of lighting bubs will come to different sizes. Therefore, we designate the shape of the bulbs with LETTERS-NUMBER format. The letters of these designations (A, C, G ETC) is referring to the actual shape of the bulb itself. The number is the measurement of the bulb’s diameter at its widest point, and this is expressed in 1/8ths of an inch or expressed directly in millimeters in some countries.

The Most common used bulbs shape for ordinary Led lighting bulbs:

The Most common used shapes for Led candelabra lighting bulbs:

led candelabra bulbs shapes

The Most common used shapes for Led filament lighting bulbs:

Led filament bulbs shapes

The Most common used shapes for Led spotlight bulbs:

Please check out the list of the sizes that are available for each of the eight most common light bulbs in the market:

  1. Arbitrary (A15, A17, A19, A20, A21, A23)
  2. Globe (G9, G11, G12, G16, G16.5, G19, G25, G30, G40)
  3. Candle (C6, C7, C9, C11, C15 or C35 C37)( C35,C37 is the metrics in millimeters)
  4. Multifaceted Reflector (MR8, MR11, MR16, MR20)
  5. Blown Reflector (R12, R14, R16, R20, R25, R30, R40)
  6. Bulged Reflector (BR25, BR30, BR38, BR40)
  7. Parabolic Aluminized Reflector (PAR14, PAR16, PAR20, PAR30 Short or Long Neck)
  8. Tubular / straight tubular ( T37,T42,T60,ST18 ETC)