Speras E21 Titanium Flashlight Review

Speras E21 Titanium Flashlight Review

The Speras E21 titanium flashlight is a 21700 cell light running a single Luminus SST-40 emitter. The tactical E21 has a neat dual-action switch. Read on!

Official Specs and Features

Here’s a link to the Speras E21 titanium flashlight product page.


A number of colors of Speras E21 are available. Those include black, red, green. There’s also metal options: aluminum and titanium (seen here). A few kit options or accessories are available, too – a GM1 mount, a RMC V2 Type C remote pressure switch, and all of it is available as a kit (in the aluminum E21 body), too.


The Speras E21 titanium flashlight sells for $109 and is available now.

What’s Included

Speras E21 Titanium flashlight what's included

  • Speras E21 titanium flashlight
  • Charging cable (USB to USB-C)
  • USB-C to female USB for powerbank usage
  • Lanyard
  • Manual

Package and Manual

Speras E21 Titanium flashlight label sticker

Speras E21 titanium flashlight manual Speras E21 titanium flashlight manual

Build Quality and Disassembly

Speras E21 Titanium flashlight

I’ve tested the aluminum Speras E21 and it’s a very nice light! Good enough that I requested this titanium version from Speras (and also because now I get to show the full kit, not just the Kickstarter preview version).

The Speras E21 titanium flashlight is well built and solid. Not much more to say about build quality here (more later on specifics).

The E21 in titanium specifically (but not necessarily all Speras lights) has one specific downside: the cell is built in. As far as I could tell, the parts do not separate at all (at least with consumer-level effort.)

Size and Comps

Length: 128mm
Head and tail diameter: 25.4mm
Weight: 135g (including the cell of course, since it’s built in) (this weight is probably for the aluminum version though.)

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

Speras E21 Titanium flashlight in hand

Here’s the test light with the venerable Convoy S2+. The version you see below is a custom Convoy S2+ host that’s been laser engraved by GadgetConnections.com. I did a full post on an engraved orange host right here! Or just go straight to GadgetConnections.com to buy your Convoy S2+ now!

Also above is the light beside a TorchLAB BOSS 35, an 18350 light. I reviewed the aluminum version of that light in both 35 and 70 formats. I also reviewed that specific edition, the “Oveready BOSS FT Collector Vintage Brass” 35. I love it!

Retention and Carry

A pocket clip is included and attached from the factory. It’s a fairly standard two-way friction fit clip.

Speras E21 Titanium flashlight pocket clip

Attachment seems secure enough, but the clip is removable.

As you can see above, the clip has a hole in the shoulder to attach the included lanyard. This is the only place to attach the lanyard.

Speras E21 Titanium flashlight lanyard

Nothing else is included for carry of the E21.

Power and Runtime

Power is provided to the E21 by a built-in 5000mAh 21700 cell. As far as I know, the cell is not user-replaceable. Obviously the cell went into the light somehow, so with the right attitude you might be able to swap it. But in general, you won’t be doing this in the field.

Three runtime tests are below. Turbo steps down pretty quickly, but still holds around 1500 or so lumens for a full minute. That’s pretty good.

Speras E21 Titanium flashlight runtime chart

Speras E21 Titanium flashlight runtime chart

Speras E21 Titanium flashlight runtime chart

Speras E21 Titanium flashlight runtime chart

When the cell voltage is low, an indicator near the charging port blinks red. The indicator is right at the pivot point of the charging port cover, but is conspicuous when blinking red.


Of course with a built-in 21700 comes built-in charging. This charging is by way of a USB-C port on the head end of the Speras E21 titanium flashlight.

A cable is included: USB to USB-C.

Speras E21 Titanium flashlight charging cable

Charging works just fine, and is brisk at around 2.75 hours.

Speras E21 Titanium flashlight charging graphs

While charging, the red indicator (the same one that activates during runtimes) blinks red. When charging is complete, this indicator stays lit in green.


The USB-C charging port can also discharge the built-in 21700 – it can serve as a powerbank. Speras includes this male USB-C to female USB adapter, so you’d be able to use your common cables for phone charging or whatever. But C to C output works fine too (and in fact, is what I tested.)

Speras E21 Titanium flashlight powerbank adapter

The USB-C port can output around 3A but is most comfortable around 2A (as the manual says).

Speras E21 Titanium flashlight powerbank graph

When the cell gets low, the powerbank will shut off. It does seem to continue pinging the output, but that is probably just my test equipment. Anyway, the powerbank feature works fine.

Speras E21 Titanium flashlight powerbank graph

Modes and Currents

Mode Mode Claimed Output (lm) Claimed Runtime Measured Lumens
Turbo 2000 4h 1780 (os)
1480 (30s)
High 900 5h 900
Medium 350 8h 370
Low 100 26h 106
Eco 10 220h 13.6

Pulse Width Modulation

The sawtooth observed below is probably not real PWM, and is so fast you’re very unlikely to see it anyway.

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, comparing them to the test light will be easier. Unfortunately, the PWM on this light is so bad that it doesn’t even work with my normal scale, which is 50 microseconds (50us). 10ms. 5ms. 2ms. 1ms. 0.5ms. 0.2ms. 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.

User Interface and Operation

A single switch controls the Speras E21 titanium flashlight. This switch is a very proud tactical “mechanical” switch – I say “mechanical” because I’m not sure. The clicky action feels mechanical but the side action is unusual for a mechanical switch.

Speras E21 Titanium flashlight tail switch

Speras E21 Titanium flashlight tail switch actuation

Action both ways are just fine – the clicky is positive and the mode changes work great, too!

Here’s a UI table! The E21 has two “patterns” (or groups). They’re similar but provide different access – best for tactical or best for outdoor uses.

State Action Result
Off Tactical Pattern Tap Momentary Turbo
Off Tactical Pattern Click Turbo
Off Tap “Sub tail” Strobe
On Click Off
On Tap Sub tail Mode advance (Eco>L>M>H>T)
On Tactical Pattern Hold Sub tail Momentary Strobe
Off Outdoor Pattern Click On – Mode memory (LMH only)
Off Outdoor Pattern Tap Momentary Mode Memory(LMH only)
Off Outdoor Pattern Tap Sub tail Momentary Eco (the manual has this wrongly listed as “turbo”)
Charging Tap Sub tail 3x Changes pattern (Outdoor or Tactical) with blinks to indicate (Tactical: 4 blinks. Outdoor: 3 blinks)
Off Tap Sub tail Battery indication LED beside charging port^
Off Tap Sub tail 6x Lockout (Main emitter blinks to indicate)
Lockout Tap Sub tail 3x Unlock

^ Battery indicator as follows:

Green: >70%
Orange: 30-70%
Red: 5-30%
Red flashing: <5%

LED and Beam

Speras has used a single Luminus SST-40 emitter in the E21. It’s rated at 6000K-6500K and has a small smooth reflector.

Speras E21 Titanium flashlight emitter

Speras E21 Titanium flashlight reflector

The very toothy bezel allows light to escape while headstanding, and more importantly, plays into the tactical feel of the E21. Also below you can see the power indicator.

Speras E21 Titanium flashlight toothed bezel

Speras E21 Titanium flashlight emitter on

LED Color Report (CRI and CCT)

Speras seems to have safely estimated the CCT on this Luminus emitter – I read it from 5600K to around 6500K. That’s sort of “neutral” to “cool.” CRI is low at around 68.


These beamshots are always with the following settings:  f8, ISO100, 0.3s shutter, and manual 5000K exposure. These photos are taken at floor level and the beam hits the ceiling around 9 feet away.

Tint vs BLF-348 (KillzoneFlashlights.com 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 KillzoneFlashlights.com 219b BLF-348 because it’s inexpensive and has the best tint!

Summary and Conclusion

The Speras E21 titanium flashlight has, among other features, a very neat dual-action tactical tail switch. The switch has a typical mechanical clicky action and is very exposed (so very tactical) but also has a side push option for mode changes. I like the switch. Output is great too, and the feature set (including USB-C charging and a powerbank) make this a great light. The aluminum version is fine but the titanium version really shines. The stonewash finish is great!

The Big Table

Speras E21 titanium flashlight
Emitter: Luminus SST-40 (Cool White)
Price in USD at publication time: $109.00
Cell: 1×21700
Runtime Graphs
LVP? Red blink warning
Switch Type: E-Switch
Quiescent Current (mA): ?
On-Board Charging? Yes
Charge Port Type: USB-C
Charge Graph
Power off Charge Port Eco only
Claimed Lumens (lm) 2000
Measured Lumens (at 30s) 1480 (74% of claim)^
Candela per Lumen 13.59
Claimed Throw (m) 322
Candela (Calculated) in cd (at 30s) 847lux @ 5.498m = 25603cd
Throw (Calculated) (m) 320.0 (99.4% of claim)^
Claimed CCT 6000-6500
Measured CCT Range (K) 5700-6200 Kelvin
Item provided for review by: Speras
All my Speras 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 I like

  • Nice build quality
  • Interesting type of two-stage or dual-action switch
  • Good beam profile
  • User interface is simple
  • USB-C charging works well
  • Powerbank function

What I don’t like

  • Built-in 21700 (can’t be replaced)
  • Released through Kickstarter


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