REVIEW: Nitecore EC23 (XHP35 HD w/Beamshots, Runtimes)


Flashlight Enthusiast
CPF Supporter
May 27, 2016
What do you get when you take the Nitecore Concept 1, keep the Cree XHP HD E2 emitter outputting almost 2000 lumens at turn on, the smooth reflector, momentary turbo, and the one-button operation – but repackage it into a light that is more rugged, foregoes the tail magnet, has better heat management, and a traditional side switch?
The Nitecore EC23.


Here is a summary of the EC23 as tested, for those not inclined to read the full review:

Skip to the commentary section at bottom to read my subjective notes on the EC23 and differences from the Concept 1.

My Concept 1 review posted previously can be found here:

Disclaimer: This light was provided free of charge by Nitecore Store for review, as was the Concept 1.


The EC23 is packaged in a black and yellow retail box in the same style as other Nitecore flashlights. It’s a very familiar design. The 1800 lumen output, XHP35 HD LED, 18650/CR123A battery compatibility, and ultra-compact size are advertised on the box front.

The right side has the EC23’s specifications.

The left side has the model number, an image of the light in use, and touts the EC23 as a “One-handed operation High Performance Flashlight.”

The back of the box promotes some of the EC23’s features.

Inside the box, a plastic tray holds the EC23. The accessories are tucked next to the EC23 from the underside of the tray.

Included is a lanyard, manual, warranty card, and spare o-rings. No holster or pocket clip is included (though the EC23 is compatible with accessories designed for 1 inch diameter lights).

The manual is in 9 languages (English, Spanish, German, French, Polish, Japanese, Romanian, Chinese, and Korean); each language’s section is complete as the text is quite small. Nitecore has included candela and throw specifications for not just Turbo but all modes.

It is available online here:

The UI is unique, so Nitecore Store adds a Quick Start Guide of their own creation to make getting started easier.

Nitecore backs the EC23 with a 5 year warranty.


The EC23 is a slim profile single 18650 light. The head and body are 25.4 mm (1 inch) wide and overall length is 129 mm. Weight was measured at 80 g.

The EC23 has some Nitecore-specific design elements but the general profile overall is quite similar to other slim single 18650 models as demonstrated by those immediately flanking the EC23.
Left to Right: Nitecore TM03, Nitecore P16 TAC, Klarus XT2CR, Zanflare F1, Nitecore EC23, ThorFire TK15S, Convoy S2+, Nitecore Concept 1, Manker E14 II.

The 1 inch width makes it compatible with a variety of accessories.

The head of light has a flat bezel, glued in place and non-removable. The advantage of the flat bezel is that it is pocket friendly. The disadvantage is that when the light is placed head-down on a flat surface, no light will escape to let the user know the light was left on by mistake.

The reflector is smooth, imperfection-free, and relatively deep given the size of the light. The glass is AR-coated.

The XHP35 HD E2 emitter is perfectly centered.

Behind the bezel on the side of the head is a “HOT” warning nicely aligned with the mode switch. Unfortunately the warning and mode switch are not aligned with the body tube’s writing.

The Mode switch is raised and easy to find in the dark. Moderate pressure is required to activate the switch; it could be activated accidentally in a pocket but not easily.

The switch is not illuminated in normal operation but a blue LED underneath is used to display battery voltage. When first connected, the switch will blink a certain number of times, pause, and then blink a certain number more. If the battery is 3.8V, for example, the EC23 Mode switch will blink 3 times, pause, then blink 8 times. Oddly, a fully-charged battery is reported as 4.1V (rather than 4.19V rounding to 4.2).

The mode switch will also blink once every 2 seconds once the battery is under 50% and blink rapidly once under 10%.

Registration and disposal information is printed on the opposite side of the head. The writing is larger than it needs to be.

The Nitecore Logo and website are located on one side of the battery tube.

The other side of the battery tube has the EC23 model number.

Knurling is mild. Anodization (HA III) is consistent and free of defects.

Rather than a simple one-plane flat design, the tail has an protruding ring –as if it was protecting a tail switch. This initially seemed a bit strange, but I found it does help it to tail stand on slightly uneven surfaces (like rocks) better than completely flat designs.

The dual lanyard holes and notch allows the lanyard to be attached without compromising tail standing.

The EC23 disassembles into 3 sections – head, body tube, and tail. O-rings are present on both ends of the body tube, as necessary for the IPX-8 (2m) water ingress rating.

Threads are square cut and very well lubricated. They are also anodized, so a quarter turn of the tail will mechanically lock out the EC23.

The tail cap has a substantial gold-colored spring.

The head has a single raised post, so both button top and flat top cells will work. The EC23 requires a battery capable of at least 8A for Turbo mode; electronic reverse polarity protection and low-voltage shut-off means that unprotected cells can safely be used.


The smooth reflector produces a defined hotspot and corona. The spill is still bright enough to be useful, though.

The tint is typical for the XHP35: the hotspot is a nice creamy neutral, the corona is yellowish, and the spill has some tint shift towards cooler blue. I’d estimate temp ranges from around 4700 to 5700K.

Notice the general consistency between the XHP35 lights shown.
Left to Right: Nitecore Concept 1, Nitecore EC23, Klarus XT2CR.

To demonstrate the overall color balance, here is the EC23 flanked by lights with emitters of various tints and temperatures.
L to R: Convoy S2+ with cool XM-L U2 1B, Nitecore Concept 1 with XHP35 HD E2, Nitecore EC23 with XHP35 HD E2, Astrolux S41S with neutral 219B, Lumintop Tool with warm 219B.

Nitecore rates the EC23 at 1800 lumens on Turbo when used with an 18650 capable of 8A or higher. (If a lower output 18650 battery is used, the cell’s protection is likely to trip and render the light useless until the battery is removed and reinstalled.) CR123A primary cells can also be used with the EC23, though Turbo will be absent from mode rotation.

Like the Concept 1, the EC23 has Nitecore’s “Advanced Temperature Regulation module” designed to keep the LED from overheating. It is very active in both lights.

I tested Turbo with the recommended Nitecore IMR18650 3100mAh 10A cell and measured initial output at 1910 lumens. Based on the starting temperature of the light, environmental temperature, and airflow, testing results at 30 seconds varied.

In a “normal” test at 76 degrees Fahrenheit with an 80mm PC fan in place to provide some airflow, output was 1483 lumens at 30 seconds. This is about 100 lumens more than the C1 in the same conditions.

After the initial drop, output levelled off around 1000 lumens by minute 5 before ever-so-slowly declining until minute 64 – when output dropped from 915 to 328 lumens. At minute 75 another stepdown occurred to 90 lumens – making ANSI runtime as tested 1 hour and 15 minutes. Nitecore calculates Turbo at 30 minutes, so runtimes as tested to 50% (1:06) and 10% (1:15) both exceed Nitecore’s specifications.

The EC23 remained functional at 2 lumens for over 3 more hours before powering off.

To illustrate the importance of temperature, the test was repeated with a warm light and no supplemental airflow. The light dropped to under 1000 lumens 3 times faster and settled in at an output 400 lumens lower! Peak temperature near the head was also 122F – 11 degrees warmer than with the fan.

When the Concept 1 and EC23 are both fan cooled, the EC23 maintains a higher output. Heat will limit Turbo for both lights, but the EC23 manages the heat better than the smaller and lighter weight Concept 1.

High is rated by Nitecore at 980 lumens. I measured 1035 lumens at turn on and 1026 at 30 seconds. The light held 960 lumens or more until minute 62 – when a stepdown to 326 lumens occurred. Another stepdown occurred at minute 76, reducing output to under 10%. This runtime (1:16) matches Nitecore’s specification of 1:15 (75 minutes) closely.

As with Turbo, another 3 hours at 2 lumens followed before the EC23 powered off.

Medium is rated at 300 lumens. I measured 331 lumens. Output was flat at that level until a stepdown to 90 lumens occurred at 4 hours and 23 minutes into the test. Another occurred at 4 hours and 35 minutes, reducing output to only 2 lumens. A runtime of 4:35 exceeds Nitecore’s 4:15 rating slightly.

Low is rated at 55 lumens. I measured 88 lumens. It held this output until 17 hours and 57 minutes into the test – falling a little short of Nitecore’s 20 hour rating.

Finally, Ultralow (moonlight) is rated at 1 lumen. I tested it at 2.1 lumens. Runtime was not tested.

All outputs:

All runtimes tested:

All runtimes tested, first 70 minutes:

CR123A batteries were not tested for runtime or output. Note that Turbo mode is unavailable when using CR123As. The full output and runtime chart for CR123As is available in the manual linked above.

Amperage Draw
As measured:
· Turbo: 4.7A
· High: 2.7A
· Med: 0.67A
· Low: 0.15A
· Ultralow: 11.3mA

Battery Protection
The battery’s own low-voltage protection was not tripped on any tests. The EC23’s low-voltage cut-off protected the cells from over-discharging with termination voltages between 2.94 and 3.02V.

I tested throw distance at 1.46 meters and the resulting candela was 12,938 at 30 seconds - equivalent to 227 meters of throw. Nitecore rates the EC23 at 255 meters of throw.

No PWM was detected visually or with a camera on any mode.

Parasitic Drain
The EC23 uses an electronic switch so some parasitic drain is normal, unlike with mechanical tail switches that fully disconnect the circuit when off.

Somewhat oddly, the drain is not consistent – it jumped around from 16 to 33 μA as I was measuring it over 30 seconds. Some Nitecore lights in the past like the EC4S measured in excess of 300 μA at times, so the EC23 performs much better.

Mechanical lock out (thus breaking the circuit and reducing parasitic drain to 0) is possible by simply unscrewing the tail cap a quarter turn. This should be done if the light is to be stored for a very long time period.

Outdoor Beamshots

All photos taken with a Canon SD4000IS camera. 1/4" exposure, ISO800, Daylight white balance, F2.0.
Approximate distances: White deck railing @ 15 ft., white fence in distance @ 75 ft., center of boat @ 100 ft.

Control shot:




(Not the best picture; will attempt to retake.)



The interface is a bit unique, but it allows direct access to Ultralow and Turbo modes as well as the last used mode (mode memory).

From off:
  • Short press the switch to turn the light on to the last mode used
  • Press and hold the switch 0.5 seconds to turn on Ultralow (Moonlight)
  • Press and hold the switch 1.5 seconds to turn on Turbo
From on:
  • Within 1.5 seconds of turning on, press and hold the switch to cycle upward through the 5 modes
  • After 1.5 seconds of turning on, press and hold the switch to access momentary Turbo
  • Triple press to activate strobe
    • Press and hold for 1 second to cycle Strobe->SOS->Beacon
    • Short press to resume the last used normal mode
  • Short press the switch to turn off
  • Fully press the tail switch to turn off

All normal modes are memorized. Direct access to Ultralow and Turbo does not override the memorized level. Strobe, SOS and Beacon modes are not memorized.

Note that the interface is slightly different than the Concept 1 as the C1 requires a double-click to access Ultralow from off and a triple-click to access Turbo.


No problems were experienced while testing the Nitecore EC23.


I opened this review comparing the EC23 to the Concept 1, and I think it’s fair to close the review the same way. The two Nitecore lights are very similar, having the same emitters and modes/outputs as tested. Both lights have very high outputs for the size.

The Concept 1 is a modern-looking light that puts that form above function. The EC23 is a traditional-style light that puts function first. It manages heat better, is thicker and stronger throughout, has a more practical switch, is less likely to be turned on accidentally, is cheaper, and still retains the strong output and useful mode spacing. It is notably larger, though still pocketable.

The interfaces are slightly different; the EC23 has the advantage as a single press will turn the light on (rather than a long press required for the Concept 1; a single press does nothing). Otherwise the two are equally capable in that they allow Ultralow, last used, and Turbo modes to all be accessed from off. Press-and-hold for momentary Turbo (from on) is also handy when ~1800 lumens are needed for short periods. Not being able to change modes once the light has been on for a few seconds without having to first turn the light off can be a little frustrating and may scare off some potential buyers.

The lack of a pocket clip on the EC23 may also leave some users wanting, though snap-on clips for other 1 inch diameter lights will likely work.

Locking the light out at the tail cap is still recommended, though not quite a critical as with the Concept 1 as the switch requires more force to activate.

Overall the EC23 is a very powerful narrow-head single 18650 flashlight. Turbo is for best for bursts only, but momentary Turbo access from any mode is convenient. Overall it is similar to the Nitecore Concept 1, but repackaged to add practicality. The emitter tint, unique UI, and lack of pocket clip should be considered when purchasing.

Lux Meter: Dr. Meter LX1330B
Integrating "sphere": Homebuilt tube-style device calibrated on other known lights and test results. Numbers should be considered relative to each other and my other review figures but accuracy is in no way certified or guaranteed.

Camera: Canon SD4000IS
Multimeter: Craftsman 82170

Last edited:


Mar 20, 2016
Excellent review BDM82 as always. well done.

I shall get one of this soon.
Thanks again


Newly Enlightened
Oct 20, 2017
I got mine couple of weeks ago, I really like the light.
However, I can see a dark mark in the center of the light pattern while I am close to a wall or some other object.
It is notable but not bothering me too much to be unhappy with it.
It was even lighter and smaller than I thought.
The UI reminder me of some Olight, I like the UI better than tail click only light.


Flashlight Enthusiast
CPF Supporter
May 27, 2016
Excellent review BDM82 as always. well done.

I shall get one of this soon.
Thanks again
Thanks proceed, I appreciate it!
I got mine couple of weeks ago, I really like the light.
However, I can see a dark mark in the center of the light pattern while I am close to a wall or some other object.
It is notable but not bothering me too much to be unhappy with it.
It was even lighter and smaller than I thought.
The UI reminder me of some Olight, I like the UI better than tail click only light.
The emitter is a quad die style so there's a natural crosshair pattern. However it is small and not noticeable unless really really looking for it, at least in my sample. Lights with the larger XHP70 emitter show this effect much more than this one.

It'd be great if you could post a pic so we could see what yours looks like.


Newly Enlightened
Dec 17, 2017
Ah, the journey begins. I ordered mine now. Great review and write-up. Thanks!


Flashlight Enthusiast
Jul 23, 2007
Bozeman, Montana
Great review! Very well done and more than thorough!

As much as I want to buy one, NO CLIP AND NO HOLSTER? Deal breaker for me.

I think one or the other should be included.

Thanks foenthe defailed review 👍🏼


Flashlight Enthusiast
CPF Supporter
May 27, 2016
Great review! Very well done and more than thorough!

As much as I want to buy one, NO CLIP AND NO HOLSTER? Deal breaker for me.

I think one or the other should be included.

Thanks foenthe defailed review 👍🏼

Yep, a lanyard is all you get.
That said, it's a 1 inch barrel, a common size, so you might have a compatible clip or holster on another light.


Newly Enlightened
Feb 17, 2018
Great review. I picked this up shortly after it came out, it hasn’t seen much use though from me due to the switch. For me it’s a PITA switching modes. I’ll be glad when they release a version with the tail switch and a 2button mode switch on the head like the MT10A.