REVIEW: Nitecore MH23 Flashlight

The Nitecore MH23 is a rechargeable, single 18650-based flashlight that reaches up to 1800 lumens and nearly 300m of throw whilst maintaining a profile still friendly for most pockets. A dual-stage, backlit side switch controls the MH23’s many modes. It has the same shape and general dimensions as the less powerful MH20 it replaces.

Here are the key specifications as tested:

Pros:

  • Direct access to Ultralow, Turbo, and last used modes
  • Generally delivers on rated specifications
  • Pocket clip, holster, and lanyard all included
  • Integrated battery charging via micro USB
  • No PWM

Cons:

  • Battery can’t be “topped off”
  • Turbo output cannot be sustained very long
  • Slower charge rate

Skip to the commentary section at bottom to read my subjective notes on the MH23.

Disclaimer: This light was provided at no cost by Nitecore Store, shipping from their location in Texas. Nitecore Store is an authorized Nitecore distributor for the U.S.A. Retail price at the time of this review was $99.95.


Unboxing

The MH23 arrived in the traditional black and yellow Nitecore retail box.

The rear:

Specifications on one side:

And an image of the beam and the output/throw numbers on the other side:

Inside the box, a plastic tray holds the MH23, pocket clip, holster, lanyard, micro USB cable, warranty card, spare gaskets, spare o-rings, spare charge port cover, and manual.

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 online here:

Nitecore backs the MH23 with a 5-year warranty.


Design

Nitecore bills the MH23 as a “palm sized spotlight;” this is achieved through a compact body and slightly larger head.

Nitecore lists the length at 111.3 mm, head width at 31.8 mm, body width at 25.4 mm, and weight at 96.2 g. My measurements confirmed these specs to the nearest half mm/g.

For a size comparison, here is the MH23 with other flashlights (and the batteries they use). The MH23 is on the shorter size for an 18650-based light, though the head is wider.

L to R: Olight R50 Pro (26650), Zanflare F1 (18650), Nitecore EC23 (18650), Nitecore Concept 1 (18650), Nitecore MH23 (18650), Emistar D1 (18650), Manker E11 (AA), Olight R1 (16340), Lumintop Tool (AAA).

Starting at the front, the head has a flat black bezel stainless bezel and deep, smooth reflector. The reflector was nice and free of any imperfections with only faint machining marks. The bezel is not removable by hand.

The lens is AR-coated. The XHP35 HD LED is well-centered.

On one side of the head is a HOT warning – aligned directly above the switch.

The switch is a transparent rubber circle surrounded by a metallic ring. The switch boot is easily serviced, and is backlit in blue when charging or reading out battery voltage.

On the other side is safety registration and disposal information, again, aligned properly above the charge port.

The charge port cover rotates fully out of the way when open, providing excellent access to the micro USB charge port. A spare cover is also included.

Around the switch and charging ports are flat spots interrupting the shallow cooling fins. These flat spots prevent the MH23 from rolling away on moderately flat surfaces.

The short body tube has a fine diamond-pattern knurling. A flat spot on one side features the model number; the other side has Nitecore’s logo. Thread length on the head end of the body tube is longer than the tail end – so the MH23 will not work if the body tube is backwards.

The tail cap has a side-facing lanyard attachment point. This design allows a lanyard to be attached without compromising the light’s ability to tail stand. The hole is also wide enough to thread the lanyard by hand with some patience.

Inside the tail cap is a single gold-colored spring. The tail cap itself is long – the outer bare metal ring is as far as the cap screws onto the battery tube though the battery has more room inside the cap. (I initially thought an 18650 was too long due to how much it protruded past the end of the battery tube with the cap off – but this is normal.)

At the head end there is no spring, only a solid post. Note that there is no secondary post to require button-top batteries – Nitecore allows flat-top batteries with the MH23 as IMR18650 batteries with discharge capabilities >8A are recommended. (RCR123/16340 and CR123A batteries can also be used though Turbo will not function.)

Threads are square-cut, nicely lubricated, and anodized both head and tail. Backing off either one slightly will mechanically lock the light out.

Accessories

Pocket Clip

The MH23’s pocket clip is designed for head-down deep pocket carry only. While there appears to be space for the pocket clip to attach on the other end of the batter tube, reorienting the clip, the wider head of the MH23 and the extended hairpin end of the clip come in contact with each other before the clip can seat on the tube.

Holster

The holster is the same quality holster design that accompanies many other Nitecore lights. A hook-and-loop flap keeps the MH23 secure, either head up or head down. A d-ring, belt loop, and hook-and-loop flap on the back provide multiple carry options.

Lanyard

The lanyard is of good quality with a tight knit rope that’s threaded through the tail cap and a comfortable neoprene wrist strap.


Performance

Beam
The XHP35 HD and smooth reflector produce a sharp hotspot, cloudy corona, and wide but dim spill.

Tint & Temperature

The color and CCT are not specified by Nitecore. I found the hotspot was slightly cool (about 5900K) with an ever-so-faint amount of blue. The cloudy corona was warmer (about 5100K) with a definite yellow tone. The spill was very cool (>6500K) and visibly blue tinted, though I found this not as noticeable outdoors because the spill is not that bright. In fact, the corona’s more neutral colors tend to catch the eye most in real-world use.

To demonstrate the overall color balance, here is the MH23 surrounded by lights with emitters of various tints and temperatures. Camera W/B set to daylight.

L to R: Convoy S2+ (cool XM-L2 U2 1B), Jetbeam C8R (cool XM-L2), Nitecore MH23 (XHP35 HD), BLF348 (neutral 219B SW50 R9050), Lumintop Tool Cu (warm 219B).

The Nitecore EC23 and Concept 1 also use the XHP35 LED. The tint and temperature is consistent across all 3 models, though the hotspot is tighter on the MH23 due to the larger reflector.

Output

Note: Separate runtimes are specified by Nitecore for 3100mAh IMR18650, 3500mAh 18650, and 2xCR123 cells. Turbo is not accessible with CR123 cells. 18650 cells used must be capable of 8A.

All testing was performed with the 3100mAh IMR18650 cell and ambient temperature of about 70 degrees.

Turbo is rated for 1800 lumens and 30 minutes. Turbo can be activated in normal mode rotation – or in momentary mode by half pressing and holding the button from another mode. Performance varied considerably between these two Turbo modes.

In momentary mode, turn-on was 1806 lumens and 1746 lumens at 30 seconds. Over 1725 lumens were maintained until a hard step-down by 45 seconds. Full runtime was not tested.

In mode rotation, Turbo started at 1765 lumens and was down to 1234 lumens at 30 seconds. Under 80mm PC fan cooling, a fairly linear decline followed until a stepdown at minute 66. 10% output was reached at minute 73 – dramatically exceeding the 30 minute specification. The MH23 eventually powered off at 3:15. Nitecore’s Advanced Temperature Regulation (ATR) means real-world performance will vary some based on conditions. Max temperature recorded at the head was 122.5F (50C).

First 45 seconds for both Turbo methods:

Full Turbo runtime (from mode rotation):

High is rated at 760 lumens for 1:45. I measured 864 lumens at turn on and 855 at 45 seconds. Output was flat at about 839 lumens for 78 minutes – when the first stepdown occurred. The second stepdown was at minute 87, reducing output to under 10%. This runtime of 1:27 falls a little shy of the 1:45 specification, though the output was higher than specification. The MH23 eventually powered off at 5:16.

Medium is rated at 260 lumens for 4:45. I measured 303 at turn on and 301 at 30 seconds. Output was very flat until a stepdown at 4:46 – producing a runtime perfectly in line with specification. The MH23 powered off at 7:41.

Low is rated at 55 lumens for 19 hours. Output was tested at 74 lumens. Runtime was not tested.

Ultralow is rated at 1 lumen for 300 hours. Output was tested at 1.7 lumens. Runtime was not tested.

All output levels:

All runtimes tested:

Amperage Draw

As measured with a Nitecore IMR3100:

  • Turbo: 5.35A
  • High: 2.15A
  • Med: 0.58A
  • Low: 0.13A
  • Ultralow: 14.4mA

Throw

I tested throw distance at 1.46 meters with Turbo in mode rotation and the resulting candela was 18,033 at 30 seconds - equivalent to 269 meters of throw. Nitecore’s specifications are 26,600 and 294 meters. This discrepancy is tied to the overall output drop over the 30 seconds as seen with the Turbo Runtime graphs; initial output and when in momentary mode is indeed higher.

PWM

Nitecore advertises the MH23 as constant current – and I found no signs of any PWM during testing.

Internal Recharging

Charging is possible with any micro-USB cable and a power supply of at least 0.5A. The MH23 (based on an inline USB meter) charged at up to 0.54A, with a reduced amperage as the cell was nearly full. A fully depleted cell will therefore take about 7 hours to recharge – this is not a fast charge.

The voltage readout (via the side switch when the battery is inserted) never indicated a full 4.2 V after the internal charger was used. The internal charger terminated at 4.18 to 4.19 V and the readout appears to truncate rather than round (blinking 4+1 times when fully charged). If an external charger (that charged to 4.2 V) was used, the MH23 does in fact readout 4.2 V.

The other interesting discovery is that the MH23 will not charge the cell if the cell is at 4.10 V or above. The MH23’s switch light will remain solid indicating a fully-charged cell – though the cell is not full.

Parasitic Drain

The dual-stage switch is electronic, so some parasitic drain is to be expected. What I found interesting is that it would rest at 170µA yet occasionally jump to >4mA less than a second before returning to about 170µA. For this reason, a true measurement was not obtained.

Low Voltage Battery Protection

The MH23 powered when the battery reached between 2.91V and 3.03V across various tests. This is in line with a safe 2.8-3.0V cutoff voltage and makes it safe to use a variety of unprotected cells.

Impact Resistance

Nitecore rates the MH23’s impact resistance at 1.5 meters. This was not tested.


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, back of dock @110 ft.

Control:

Ultralow:

Low:

Med:

High:

Turbo:


Interface

The MH23 has 5 regular modes with mode memory, 3 special modes (Strobe/SOS/Beacon), and a switch-flashing position indicator mode.

From off:

  • Half press to activate the position indicator (switch light flashes every 2 seconds)
    • Half press again to deactivate.
  • Half press and hold the switch for 0.6 seconds to access Ultralow.
  • Full press to access the memorized mode.
  • Full press and hold to access momentary Turbo.

From on:

  • Half press to cycle upward through modes.
  • Half press and hold to access momentary Turbo.
  • Full press to turn off.
  • Full press and hold to access Strobe.
    • Half press to cycle Stroble/SOS/Beacon

Problems

No problems were experienced with the Nitecore MH23 while testing.

Commentary

I really like the MH23 package. I don’t just mean the box; I mean the MH23, what it does, and what it comes with (everything but a battery). It delivers a nice balance into single light.

The light is small and pocketable – yet has a big enough reflector to reach out a couple hundred yards. It can be carried in a pocket with or without a clip yet includes a holster and lanyard. It offers direct access to both Turbo at 1800 lumens (though not for long) and Moonlight mode. Output steps down long before it shuts off, ensuring no surprises when running low on battery. It has actual voltage readout via the side switch and terminates at a safe voltage. Though not fast, it has internal micro USB recharging. The position indicator mode that flashes the side switch makes it easy to find the MH23 in the dark. It has no PWM, has square-cut threads, an A/R-coated lens, a centered LED, and works with button and flat top cells.

In other words, the MH23 manages to strike a good balance of size, features, and power. It’s a good light that’s got a lot going for it. For $99.95, though, it should - this is not a budget light!

It would be better if the Turbo mode in rotation was as powerful as the momentary Turbo mode. Ultralow/moonlight mode is a little bright; some users prefer under 1 lumen for the lowest mode. The fact that it won’t top off the battery if voltage is about 4.1 V or higher is a little annoying. It does have more parasitic drain than some lights, though hard to measure due to its inconsistency. In these ways, the MH23 is not perfect.

Still, it is a well balanced, feature-packed rechargeable light with strong output and respectable throw for one that fits in a pocket.

Testing equipment

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

Micrometer: Mitutoyo CD-6ASX

Multimeter: Craftsman 82170

Nice review. They should make a xhp HI version as well.

Thanks! And yeah, a HI version of the XHP35 would certainly add some more throw; if we see an MH23GT released at some point I can bet that’s what’ll be in it.

Has anyone else recognized some kind of a dark spot (“donuthole”) in the center of the spot? When doing a whitewall shot with my MH23 I definitely see a less bright area right in the middle of the spot. It’s not as bad as the XHP70 but it’s still visible in all brightness modes from 1 to 5. It only disappears when being closer than 1,5m from the wall but it will not disappear even when I am farther away from the wall, e.g. 6m. I checked the LED by looking through sunglasses into the light (mode 1) and all four die areas had the same brightness.

Has anyone an idea what this is supposed to mean? Is a slight donuthole normal for an XHP35 HD? I never saw anything like it in reviews with beamshots.

I just found this light, while research8ng older nitecore "MH" models. I've read great th8ngs from members like lightbringer and others about the mh line. Does anyone know, dot hey make this mh23 in a nuetral white xhp35? I could always swap it out with one, but for $100 I'd like to just ge5 what I want. I really like the idea of a pocket carry with the xhp35. Thrunite and zebra light are the only ones that come to mind that use it. Beside nitecore of course.

In Nitecore parlance, anything in NW is suffixed with a ‘W’ for “warm” (ha!).

So an MH20 would be the typische Nitecore-CW, but the NW version would be the MH20W.

The light itself would still have the same “MH20” etched into it, though. Only the box would reflect the ‘W’ in the model.

Oh damn, well very good info thanks LB! So now I kno what to be on the look for!