If you have an unhealthy obssession with flashlights, you might enjoy something here.

Quick Guide to Popular LEDs

This is a guide to LEDs


  • Emitter: The component that produces light (Light-Emitting Diode in this case)
  • Die: The actual light-emitting portion of an LED
  • Phosphor: The yellowish layer seen on white emitters, this is layered on top of a blue LED and produces yellow/orange light, mixing and allowing for a true white LED.
  • Thermal Pad: Small metal pads underneath the LED that dissipate heat, and act as electrical leads
  • Dome: A silicone domelike lens on top of the die that increases output and produces a floodier beam
  • Vf: Forward voltage, the voltage at which an LED is designed to operate (usually 3v, 6v or 12v)
  • Package: The total size of the LED chip (in millimeters x millimeters)
    • Footprint: For soldering purposes, the size/shape of the electrical pads underneath the LED, expressed as mm*mm (for example, a 5050 emitter is 5.0mm by 5.0mm) - this list is organized by LED footprint
  • MCPCB: Copper or aluminum circuit board that allows the LED to be wired to the driver, and provides heatsinking
    • DTP: Direct Thermal Path, an LED + PCB construction that allows for heat to be directly drawn from LED into host. Important for high-power flashlights
  • Luminous Efficacy: The amount of light (Lumens) produced at a certain power level (Watts)
  • CRI: Color-Rendering Index, or (basically) how well colors are rendered by a light source.
    • Ra9xxx: A specific shade of red used to calculate total CRI. LEDs have a difficult time rendering reds, so this value in very important when discussing total color-rendering capability. Ra9050 is good, Ra9080 is great.
  • Temperature (CCT): Color-Correlated Temperature - how "warm" or "cool" the LED is, refers to the ratio of red to blue light in a white light source, measured in Kelvin (K)
  • Tint (duv): the ration of green to magenta in a white light source (negative is more magenta, positive is more green)
  • Monochromatic: Light emitted within a single wavelength (color) of the electromagnetic spectrum, rather than having multiple wavelengths
  • Broadband/Narrowband: In this case, when referring to colored LEDs that aren't monochromatic - basically they produce a slightly wider range of colors
  • LEP: Laser-excited Phosphor - white light produced by a blue or UV laser exciting phosphor rather than a traditional LED, very intense beam produced as a result


Cree: American brand, manufacturing done in China. Long-time most popular brand for flashlights, usually aims for high output. Their emitters do tend to have green tints, some more than others. Popular emitters from Cree include the XP-L HD and XP-L HI, XP-L2, XM-L2, XHP35(HD/HI), XHP50(.2), and XHP70(.2). Technically named Wolfspeed Inc, Cree is the LED division of the company.

Nichia: Japanese brand, and the biggest LED brand. Makes lower powered high CRI emitters. Most popular for the 219b series, loved for their absolutely beautiful tint and compatability with XP footprints. Their 219Cs were popular for a little while before the rise of Samsung's LH351 series. The 519A is a newer emitter that has gained a lot of popularity in the community as well. Other Nichia emitters that enthusiasts use include the E21A, 144A, and Optisolis series.

Samsung: You've heard of Samsung. They're a South Korean conglomerate that makes everything tech related, including LEDs. Pretty much the only Samsung emitters we use are in their LH351 series, particularly the LH351D. Depending on the bin the tint can be a bit green, but they're high CRI and just as high output as a Cree XP-L, and also compatible with an XP footprint.

Luminus: Chinese owned (originally based in California), manufactures LEDs in China. In recent years they have produced many emitters popular for flashlights, with both high-CRI and high-power options. Many of their emitters are known to be very green in tint. The SST-20 is an XP footprint emitter that throws even further than the XP-L HI, and it's available in high CRI. The SFT40 is a small but powerful LED that produces a throwy beam, while the SBT90.2 is large, extremely bright and throwy. Also common is the SST-40, which is pretty much a brighter XM-L2.

Osram: Osram is a German lighting manufacturer. We pretty much only use one family of emitters manufactured by Osram. Their Oslon series has a few emitters with long complicated names and very small dies. These LEDs are capable of high outputs, and there small emitting area means these emitters work really really well in throwers. The Osconiq LEDs are used in a few lights as well.

Getian: Chinese manufacturer, relatively new in the world of flashlights. Their GT-FC40 LED has become very popular for being a high-CRI alternative to the XHP70. More LEDs may make their way into flashlights - in particular, look out for FC15, FC30 and FC60.

San'an Optoelectronics: Another Chinese manufacturer, new to the flashlight world with their extremely high-power SFS, SFN, and SFQ LEDs. The SFN55 in particular is cabable of 10,000+ lumens. These are starting to become popular in lights that go for maximum possible ouptut, though they are known to have poor greenish tint and low-CRI.

Philips Lumileds: The massive Dutch company Philips created Lumileds, known for their LUXEON line. No longer popular in enthusiast lights, but occassionally still found in lights from brands like Olight, Fenix, and Streamlight to name a few. They do produce high-power, high-CRI LEDs, but these aren't seen in flashlights.

List of LEDs


3535 emitters:

  • XP-L HD: Domed, pretty typical when it comes to output, about 1200 lumens max. Very common. Largerly superseded by LH351D
  • XP-L2: Domed, more phosphor area than the XP-L. A bit higher output, but worse tint. Not popular
  • XP-L HI: An XP-L without a dome. More throw, less tint shift. Still bright at 1200 lumens, great natural tint with CRI 80+ versions available in warm temps. Very popular
  • XP-G2: Smaller dome than XP-L, and smaller die. Less output too.
  • XP-G3: The XP-L2 equivalent of the XP-G line. More phosphor, more lumens, worse tint. These are gross, nobody likes them.
  • XHP35 (12v): Capable of high outputs. Available in a domed high-output (HD) or domeless high-intensity (HI) version. HI version is popular for its great tint and decently high CRI (often 80+), makes for an excellent warm thrower LED in 4000K.

5050 emitters:

  • XM-L2 (3V): Similar to the XP-L, but in a slightly bigger form factor. Recently updated by Cree, newer versions are extremely efficient and even brighter than before. Once very common, but now mostly superseded by Luminus SST40 - however these may make a comeback with the new updates
  • XHP50.2 (6v or 12v): A quad-die emitter. 6V or 12V depending on how you wire it. Fairly small but efficient and very bright and floody, up to 4,500 lumens. More phosphor, more light, worse tint than the previous generation. Lookout for the upcoming XHP50.3 HD that should be available in lights soon
  • XHP50.3 HI (3v, 6v or 12v): A more efficient and domeless version of the XHP50 design, maintains very high output but with double the intensity. Supposedly available in warm white and 90+ CRI versions, should have better color than the domed version of the LED.

7070 (6v or 12v):

  • XHP70.2: Large, super floody domed quad-die LED which is very efficient and capable of extremely high outputs (easily 4,000+ and up to 9,000 when pushed hard enough). Available in nice warm color temps, and 90+ CRI versions are available in exchange for less performance. Tint is fairly neutral, though these are notorious for dramatic color shifts in the beam, with warm greenish hotspots and cool rosy spill. Lookout for upcoming XHP70.3 HD
  • XHP70.3 HI: Double the intensity of the domed version, likely with better tint. Very high output and warm white, 90+ CRI versions.


Tiny emitters (3v):

  • E21A: This is a 2121 emitter with no dome, just straight phosphor. Better beam than a 219C, but not super bright. Extremely high-CRI, Ra9080, and neutral tint that mimics sunlight. E21A quads are now largely superseded by B35A lights
  • E17A: Like the E21A, but 1717. Both of these emitters are available in a wide range of colors, from 1850K - 6500K.

3535 (3v):

  • 219B: Everyone's favorite. Not built for output, but they made really beautiful beams and available in high CRI, Ra9080. Known to have a very 'rosy' tint (negative duv), especially the SW45k bin. Small dome gives a balanced beam. These will mostly be superseded by 519a, though they are still considered the king of tint
  • 219C: The successor to the 219B. Brighter, but the tint isn't as good. Also available in high CRI. Largely superseded by Luminus SST20 and Samsung LH351D, which are brighter and high-CRI
  • 219F: Basically another successor to 219C, not meaningfully different. Does not like being overdriven. Biggest point of interest is the super-warm 1800K version that is meant to replace sodium-vapor produced light.
  • 519A: Very bright, Ra9080, pleasant neutral or rosy tint, and available in a wide range of color temps. Large dome and very floody, comparable to LH351D. Common footprint makes them easy to swap into other ligths, and they are easily dedomed for more intensity and warmer + rosier tint. Everybody's new favorite LED, expect to see them everywhere

3.65 x 3.65 (6v):

  • B35AM: Four E21A dies, this is the brightest (1300-1700 lumens depending on CCT) and throwiest ultra-high CRI (Ra9080) emitter available. Very natural, sunlight-like tint. Footprint is a bit unconventional, being 3.65mm x 3.65mm, so it requires a unique MCPCB (no DTP available, limiting max output)

5050 (6v):

  • 144A: The 144A is Nichia's answer to Cree's XHP50. Different footprint though. Also no thermal pad, so they never really caught on. High-CRI but has strong tint-shift when used without diffusion. Armytek provides the Wizard C2 Pro with this emitter.


  • LH351D: 3535, 3v, XP footprint. Big die, large dome, very floody, high CRI, very bright - excellent all-round LED. These beat out the XP-L2 when it comes to output. They tend to be about as green as a 219C, if not a bit more. This varies from bin to bin obviously. One of the few LEDs available in high-CRI cool white variants. These will likely be superseded by Nichia 519a


3535 (3v):

  • SST-20: Domed, small die. Cousin to Cree's XP-G2, much throwier (moreso than an XP-L HI) and available in high CRI and many color temperatures. Low-CRI version is very bright and throws far, while the dimmer 95+ CRI version is Ra9080. Known for weird yellowish-greenish tint, tends to be green at low currents, but bins are available with neutral or even negative duv. Very popular for its combination of performance, throw, color, and low price. Also available in a deep red version.

5050 (3v):

  • SST-40: Cousin to the XM-L2. Perfectly capable of being overdriven, up to about 9A. Easily capable of 2000+ lumens.
  • SFT40: Essentially a domeless SST40, capable of 2000+ lumens while being very throwy. Great balanced thrower and performer, but very cool (6500K), a bit green, and low-CRI.

5050 (6v or 12v):

  • SST70: Powerful domed LED, larger than SST40. Competes with XHP50.2, slightly throwier. Capable of ~4,500 lumens when driven hard. Very green at lower power.
  • SFT70: Domeless, very throwy version of SST70. Not really available yet, may be a strong SBT90.2 competitor.

9090 (3v):

  • SBT90.2: Large and extremely power-hungry LED that can produce 5000+ lumens and is very throwy. Efficient but greenish at lower powers, this is an excellent high-performance LED - but comes at a steep cost.


3030 emitters (3v):

  • KW CSLNM1.TG (White Flat): 1mm^(2) emitting area. One of the best choices if you want compact throw.
  • KW CSLPM1.TG: 2mm^(2) emitting area. Less throwy but brighter than the 1mm version, it can be pushed very hard for extremely high output when used in multi-emitter lights. Only available in 5700K, low-CRI version with nice neutral tint.

3737 (3v):

  • GW PUSTA1.PM: "Duris" series of LEDs, known as the P9 (Osram loves to make things hard apparently) - Smallish domed emitter with decently high output. Available in a range of CCTs, only really seen in cool white. Poor coloration, strong tint-shift. Brighter successor to the P8 (GW PUSRA1.PM), competes with XP-L HD with slightly better efficiency.

4040 emitters (3v):

  • KW CULNM1.TG (Boost HL): Also 1mm^(2) emitting area, same as the 3030 version. Slightly brighter though, due to larger thermal pad that can sink more heat.
  • KW CULPM1.TG (Boost HX): Same 2mm^(2) die as the 3030 version. Also slightly higher max output due to larger thermal pad.

The above emitters are also available in colored Red, Yellow/Amber, Green, and Blue versions.

View this page for more clarification on Oslon naming schemes, as flashlight manufacturers and hobbyists use a variety of names.


  • GT-FC40: 7070, 12V. A large domeless LED with 16 dies, the FC40 is very high-CRI (95+, Ra9080) that produces 4000+ lumens when driven hard, and is relatively throwy compared to domed XHP70. Available in a range of color temps including a super-warm 1800K. Looks like a waffle


Plesase note that these emitters are very new to flashlights, and while they seem to already be pretty popular, I do not know much about them. The naming schemes are pretty confusing. These LEDs seem capable of incredibly high outputs when pushed very hard, but these numbers may not be realistic in actual flashlights. Still, expect them to be very popular for powerhouse and hotrod flashlights.

3535 (3v):

  • SFS80: Comparable size to XP-L HI or CSLPM1, but much higher output; very bright (almost 2,000 lumens when pushed very hard), available in a 4000K 85 CRI version.
  • SFQ43: Supposedly even brighter, appears to be the successor to the above LED. Very green tint.

5050 (3v):

  • SFQ60: Very bright, about 3,000 lumens. Competes with Cree XHP50, but lower Vf.

7070 (3v):

  • SFH55: Huge domeless LED with 16 dies, capable of well over 10,000 lumens when pushed hard enough. Cool white and greenish. Large flat surface is somewhat floody.
  • SFN55.2: Smaller 9-die surface, about the size of the Cree XHP70.2. Small and flat surface means it's pretty throwy, and is extremely bright at ~8,000 lumens. Combination of size and output places it between the XHP70.2 and the SBT90.2. Cool white with large color variation depending on power level, low-CRI, and greenish.
  • SFN60: Supposedly even brighter than SFN55.2, apparently the successor.
  • SFP55: Massive 25-die surface, claiming 22,000 lumens from a single 3v LED! No real testing or further information yet


3535 (3v):

  • LUXEON V2: It exists. Brighter than competing XP-G2/3, 70CRI and cool white.

4040 (3v):

  • LUXEON V: It also exists, I don't think anyone cares about it though. 70 CRI, cool or neutral white, very bright ~2,400 lumens. Can take being overdriven without lasting damage. Somewhat better efficiency than SST40. Probably no reason to think about this one when the new XM-L2 exists



  • Yinding "Round LED" - a flat LED with a circular (rather than sqaure) die, very bright and impressive throw that competes with Osram throwers. Round die allows for nice beam pattern, but terrible low-CRI greenish beam.


  • LatticePower P70 - 6v. Large flat LED that is throwy and very bright. About 6500K, up to 4k lumens when pushed hard. Used in Acebeam L35.


  • Yuji 5mm LED - Classic 5mm through-hole LED design. High-CRI, available in a variety of color temps.