Convoy M21E Flashlight Review

Convoy M21E Flashlight Review

The Convoy M21E is a flashlight using a single Cree XHP70.2 emitter, and one 21700 cell. My copy is a 4000K, the light has USB-C charging!

Official Specs and Features

Here’s a link to the Convoy M21E flashlight product page.


A couple of bodies are available: black and (seen here) silver.  Each of those bodies is available with many emitter choices, too.
Cree XHP70.2 6500K
Cree XHP70.2 5000K
Cree XHP70.2 4000K (seen here)
Cree XHP70.2 3000K
Luminus SST70 6500K


Regardless of the options chosen, the price is $36.08.

Short Review

I have always loved the Convoy silver finish.  I love this one too.  USB-C charging works well, and I also really like the 4000K Cree XHP70.2 emitter.  All in all, this is a great light!

Long Review

The Big Table

Convoy M12E Flashlight
Emitter: Cree XHP70.2 (4000K)
Price in USD at publication time: $36.08 on aliexpress.
Cell: 1×21700
Turbo Runtime Graph High Runtime Graph
Switch Type: E-Switch
Quiescent Current (mA):
On-Board Charging? Yes
Charge Port Type: USB-C
Charge Graph
Power off Charge Port with cell: all modes
without cell: no modes
without body: no modes
Claimed Lumens (lm)
Measured Lumens (at 30s) 3055
Candela per Lumen 8.8
Claimed Throw (m)
Candela (Calculated) in cd (at 30s) 1019lux @ 5.367m = 29352cd
Throw (Calculated) (m) 342.6
Item provided for review by: Convoy Store on
All my Convoy reviews!

^ Measurement disclaimer:  Testing flashlights is my hobby. I use hobbyist-level equipment for testing, including some I made myself. Try not to get buried in the details of manufacturer specifications versus measurements recorded here; A certain amount of difference (say, 10 or 15%) is perfectly reasonable.

What’s Included

  • Convoy M21E flashlight
  • Lanyard (attached)

Package and Manual

Convoy M21E Flashlight box

There is no manual.

Build Quality and Disassembly

Convoy M21E Flashlight

Convoy M21E Flashlight tailcap

Convoy M21E Flashlight head Convoy M21E Flashlight cooling fins Convoy M21E Flashlight body Convoy M21E Flashlight headstanding

The threads are square-cut and beefy.  They’re also long.

Convoy M21E Flashlight head threads

Tailcap threads appear the same.  But they aren’t – the cell tube is not reversible.

Convoy M21E Flashlight tail threads

Here you can see that the driver is secured with a brass retaining ring.  The tailcap has a beefy spring, but no magnet.

Convoy M21E Flashlight driver Convoy M21E Flashlight

Size and Comps

  • Size: Head/body diameter: 45.4mm/27.3mm
  • Length: 146.5mm
  • Product weight: 166g

If the flashlight will headstand, I’ll show it here (usually the third photo).  If the flashlight will tailstand, I’ll show that here, too (usually the fourth photo).

Convoy M21E Flashlight in-hand

Here’s the test light with the venerable Convoy S2+.  Mine’s a custom “baked” edition Nichia 219b triple.  A very nice 18650 light.

And here’s the light beside my custom engraved TorchLAB BOSS 35, an 18350 light.  I reviewed the aluminum version of that light in both 35 and 70 formats.

Convoy M21E Flashlight beside torchlab boss 35

Here’s the Convoy M21E-and-a-half.

Convoy M21E Flashlight shawty

Retention and Carry

As with many Convoy flashlights, the included lanyard ships installed.  It’s installed as seen below.

Convoy M21E Flashlight lanyard installed

I consider this “wrong” and correct it to the way seen below.

Convoy M21E Flashlight lanyard installed properly

This setup allows flawless tailstanding, which I find important.

Convoy M21E Flashlight tailstanding with lanyard

Convoy M21E Flashlight lanyard holes

No pocket clip is included – in fact there is no groove on the body for a pocket clip to attach.  The lanyard holes might suffice for Convoy’s screw-in pocket clip, but all mine are out of reach (read: I have no idea where they are) so I can’t test that.  But the hole pattern looks the same, and I’m 94% sure it’d work.  Why you’d do it would be another, and better, question.

Power and Runtime

The Convoy M21E flashlight is powered by a single lithium-ion cell.  The cell tube is suited to a single 21700 cell.

Convoy M21E Flashlight with 21700

With the spring in the tailcap, you should have no issue running any type of 21700 cell.  The cell is installed in the usual way: positive terminal toward the head.

Convoy M21E Flashlight with 21700 installed

Below you can see a few runtime graphs.  Toward the end of a couple of these, I reset the light to the mode being tested.  Impressively, output reaches nearly the initial level even on Turbo, but once the cell voltage has slipped below maybe 3.4V or so, that blip of Turbo-like output is brief.

Convoy M21E Flashlight runtime graph Convoy M21E Flashlight runtime graph Convoy M21E Flashlight runtime graph

The switch has indicating features, and when the cell voltage is low the switch blinks red.


Built into the M21E is USB-C charging.  There’s a charge port in the head, on the side opposite to the switch.

The switch and charge port are a little bit too similar by feel for me, and I didn’t always differentiate between them by feel.  However, the charge port cover does have a bump-out that is discernable once you know what you’re feeling for.

Convoy M21E flashlight charge graph

USB-C to USB-C charging works, too.  In fact, it’s probably a little better.

Convoy M21E flashlight charge graph

The indicating switch works for charging just like it does for runtimes.  When the cell is being charged, the switch is red.  When charging is complete, the switch turns green.

Modes and Currents

This is for the stepped modes.  There’s ramping too, but mostly what I’ve tested is the stepped output.

Mode Mode Claimed Output (lm) Claimed Runtime Measured Lumens Tailcap Amps
100% 3055 7.05
40% 1076 1.77
10% 365 0.53
1% 27 0.03
Moonlight 13 0.01

Pulse Width Modulation

None of the stepped output levels use PWM!

For reference, here’s a baseline shot, with all the room lights off and almost nothing hitting the sensor.  Also, here’s the light with the worst PWM I could find.  I’m adding multiple timescales, so it’ll be easier to compare to the test light.  Unfortunately, the PWM on this light is so bad that it doesn’t even work with my normal scale, which is 50 microseconds (50us). 10ms5ms2ms1ms0.5ms0.2ms.  In a display faster than 0.2ms or so, the on/off cycle is more than one screen, so it’d just (very incorrectly) look like a flat line.  I wrote more about this Ultrafire WF-602C flashlight and explained a little about PWM too.

User Interface and Operation

A single e-switch controls all actions of the Convoy M21E flashlight.

Convoy M21E Flashlight switch

The switch is very low profile, but also very textured.  It’s easy to find the switch by feel, but sometimes it’s possible to confuse it with the charge port cover.

Convoy M21E Flashlight switch profile

The action on the switch is very low.

Here’s a UI table!

State Action Result
Off Click On (Mode memory)
Off Hold Moonlight (0.2% output)
Any Double click Turbo (100%)
Any Click 3x Strobe
On Click Off
On Hold Ramp˚ (in ramping mode), Mode advance (in Stepped mode)
Off Click 4x Tactical mode (Momentary 100% only)
Tactical mode Click 4x Quit tactical mode
Off Click 5x Voltage detection^
Off Click 6x Toggle between Ramping and Stepped output levels
Off Click 10x Toggle between locked and unlocked
Locked Click One blink to indicate locked status

˚Ramp will increase to the highest and blink then stop ramping.  Another hold will cause the ramp to go down.  You can perform this change of direction anywhere in the ramp.
^ Blinks ones then tens with a pause between.  Such as blink blink blink (longer pause) blink blink blink would be 3.3V.  This must be turned off – it doesn’t seem to go off after a certain number of blinks.

LED and Beam

In my review copy of the Convoy M21E is a Cree XHP70.2 emitter in 4000K.

Convoy M21E Flashlight emitter

The M21E features a smooth reflector.

Convoy M21E Flashlight reflector

Everything is accessible.  The bezel unscrews easily.

Convoy M21E Flashlight emitter exposed Convoy M21E Flashlight lens Convoy M21E Flashlight emitter Convoy M21E Flashlight bezel threads Convoy M21E Flashlight arc Convoy M21E Flashlight beamshot

LED Color Report (CRI and CCT)


These beamshots are always with the following settings:  f8, ISO100, 0.3s shutter, and manual 5000K exposure.

Tint vs BLF-348 ( 219b version) (affiliate link)

I keep the test flashlight on the left, and the BLF-348 reference flashlight on the right.

I compare everything to the 219b BLF-348 because it’s inexpensive and has the best tint!


What I like

  • Very steady output (Even 5m at 3000 lumens!)
  • Emitter options
  • Low cost
  • USB-C charging
  • Indicating switch
  • Great beam profile (relatively tight hotspot)
  • Ramping is an option

What I don’t like

  • I could stand to have a lower mode or an extra mode
  • 4000K Cree XHP70.2 has a bit of yellow
  • Only a lanyard for carry (and the lanyard, as always, is installed incorrectly)
  • The ramping speed never suited me well

Parting Shot

Convoy M21E Flashlight with sticker


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