Euri Illuminated: Choosing an LED Bulb

June 7, 2016




Original Post: Euri Lighting


All light bulbs are not created equal.

Incandescent bulbs are all but obsolete, and who wants mercury-laden CFLs in our homes?

The obvious choice is a Euri Lighting LED bulb, but now that this has been decided on, a few more facts are needed before you can march into the store and grab the first bulb you see-- Not all light bulbs are the iconic screw-in type (ie: A19 with an E26 base). So let's study the anatomy of a light bulb, and hopefully narrow down your selection to brand (Euri Lighting, ahem) and style.


Click here to understand Euri Lighting packaging, 
or click here to learn more about our product certifications.


The Bulb


Euri Lighting has an wide selection of different bulb shapes to fit your exact needs, but understanding those needs can sometimes be a bit of a challenge. To every Class Series of bulb, there are letters and numbers that mean something to those of us in the industry, but to the typical consumer it can be a bit of a mystery. What's the difference between A15 and A19? Or CA19? or BA19? Here's our summary to help you become an overnight Lighting Connoisseur.


Going backwards-- Let's start with the number.


Let's go back to that A19 and skip the A for the moment. --19-- this number that follows the letter in the sequence describes the width of the bulb, which are measured in eights of an inch (1/8 inch). So an A19 bulb is actually 2-3/8 inch at its widest point (19 divided by 8= 2, with 3 leftover).


Still lost? Let's try another:


PAR16, forget the PAR. 16 divided by 8 = 2 with none leftover, so if you measure your PAR16, it should be an exact 2 inches wide.


Ok, one more: G25: 25 divided by 8 = 3, with 1/8 leftover, making a G25 3-1/8 inch wide. Got it? It's actually a fairly simple math equation that can give you a good idea of what width bulb you need.


Now that you understand the number, let's move on to the letters.


Euri Lighting A Series Bulbs


The A Series


The A Series looks and feels like your iconic, traditional light bulb. That round and bulbous body, smooth lines, with a twisty metal base, looking like an upside-down tear drop and providing a wide beam angle. The 'A' actually stands for Arbitrary Designation, meaning it's a standard bulb for just about any application: your everyday lamp, ceiling fan, wall sconce-- it's going to work just fine!


The B Series


The B Series bulb looks and feels like a traditional Christmas Light, or, possibly, a Bullet, which is what the 'B' stands for. Many wall sconces will fit a B Series better than an A series-- they tend to run smaller in width, and delivery a wider beam angle.


The C Series


The C Series bulb is going to be shaped like a symmetrically lit candle, and is for decorative purposes only-- think chandeliers, wall sconces and lanterns.


The CA Series


Similar to the C Series bulb, the CA Series is shaped like a lit candle, but the 'flame' of the candle is poised in an asymmetrical flicker. Again, this light bulb tends to be purely for decorative purposes, and would look fabulous in fake candle chandeliers or lamps.


The R Series


The R Series bulb is a Reflector lamp, and is appropriate for recessed lighting or track lights. It has a more focalized beam angle than an A Series bulb, and has sharper angles than an A Series. R Series bulbs typically have at least some part of the bulb's surface in reflective coating to intensify the light distribution.


The MR Series


An MR Series bulb is a Multifaceted Reflector that can also be used for recessed light or track lights, or other applications that require directional lighting. MR bulbs have a completely flat glass surface, which further limit the beam angle for highly focalized light. They are typically very small compared to other Reflector bulb series. These are the perfect bulb for exhibiting art or products under glass.


The BR Series


BR Series bulbs are a bit of a mix between the R Series and MR Series. BR stands for Bulge Reflector, so there is a slightly wider beam angle than an MR Series, but less so than an R Series bulb. They are also used for spotlighting, and can often be used for outdoors applications.


The PAR Series


PAR stands for Parabolic Aluminized Reflector, and are also used in recessed and track lighting fixtures. 'Parabolic' refers to the U-shaped reflector that was traditionally used in halogen bulbs, and they create an unfocused edge to an oval-shaped pool of light. They are typically used for headlights on vehicles or for stage lighting.


The T Series


A T Series bulb is a tube, as what is typically considered a fluorescent bulb.  LED T Series bulbs, however, are better than fluorescent in that they live a lot longer, shine brighter, and won't give off that awful buzzing sound or flickering light that drives you crazy at the office.



Edison Base  |  G (Bi-Pin) Base  |  GU (Bi-Pin) Base


The Base


Now that the shape of your bulbs make more sense, let's turn to the base. Again, not all bases are equal! Read on to see which base you need and how its measured.


The Edison Base


By far, the most common bulb base is the E26 base. It's the twisty screw base that you think of for the iconic A19 bulb, and again, just like the previous numbers, the number that follows the E refers to the width of the base in millimeters. No math equation this time, an E26 base tells you that you are receiving an Edison (twisty screw) base that is 26 millimeters across. Likewise, an E12, E15, or E30 base means an Edison (twisty screw) base that is 12, 15, or 30 millimeters across. Simple!


Bi-Pin Base


The Bi-Pin was invented by Reginald Fessenden specifically for the 1893 World's Fair in Chicago, when he and the Westinghouse Corporation won the contract to wire and illuminate the fair and Thomas Edison refused to allow the patented Edison base bulbs to be used. The number that follows the letter(s) designates the spread between the center points of the pins in millimeters. 


G Base


The G base bi-pin bulb has two thin pins protruding from the bottom. The 'G' refers to the glass used in the original bulbs by Fessenden. Euri Lighting's LED Tubes utilize a G (Bi-Pin) Base.


GU Base


The GU Base is an alternative of the G Base, but is thicker with each pin looking a bit like the head of a screw. The GU Base was designed for Energy Star Program Requirements, ensuring that new, energy efficient bulbs will be used in their certified fixtures, rather than traditional incandescent bulbs. Euri Lighting's MR Series utilize a GU (Bi-Pin) Base.


Have other questions about light bulb bases? Send our sales reps an email, or give us a call-- we would be happy to help you choose the best lighting for your space!

Please reload

Featured Posts

Oatmeal Chocolate Chip Lactation Cookies That Boost Your Milk Flow and Everyone Will Love

November 15, 2019

Please reload

Recent Posts
Please reload

Content Developer, Content Manager, Lifestyle Blogger, Graphic Designer, Photographer, Model, World Traveler

© 2019 by Hannah Rothblatt-Reyes