Stainless Pen Flashlight (BLF-348) Review Stainless Pen Flashlight (BLF-348) Review

Read about one of my personal favorite lights, and reference lights, the Stainless Pen flashlight! With Nichia 219b!

Official Specs and Features

Here’s a link to the Stainless Pen flashlight product page.


There’s just one version.


The price for these confirmed 219b lights is $12.99.  It’s a bit of a premium over the 219c version, but I’d call it a good value as an absolute standard light.

Killzone hooked me up with a 10% off coupon, which will work on this light and other stuff too. The code is “Zeroair.”

Short Review

I like this one enough for it to replace the light I’ve always used for my “Tint vs BLF-348” section.  That should say enough.  It’s definitely a Nichia 219b emitter.

Long Review

The Big Table

Killzone Flashlights Stainless Pen Light
Emitter: Nichia 219b
Price in USD at publication time: $12.99
Cell: 10440
Turbo Runtime
Switch Type: Mechanical
On-Board Charging? No
Claimed Lumens (lm) 175
Measured Lumens (at 30s) 160 (91.4% of claim)^
Claimed Throw (m)
Candela (Calculated) in cd (at 30s) 65lux @ 3.589m = 837cd
Throw (Calculated) (m) 57.9^
All my Killzone reviews!


Killzone Flashlights Stainless Pen Light
Emitter: Nichia 219b
Price in USD at publication time: $12.99
Cell: AAA
Turbo Runtime
Switch Type: Mechanical
On-Board Charging? No
Claimed Lumens (lm) 175
Measured Lumens (at 30s) 45 (25.7% of claim)^
Claimed Throw (m)
Candela (Calculated) in cd (at 30s) 39lux @ 2.413m = 227cd
Throw (Calculated) (m) 30.1^
All my Killzone reviews!

^ Standard measurement disclaimer: I am an amateur flashlight reviewer. I don’t have $10,000 or even $1,000 worth of testing equipment. I test output and such in PVC tubes!! Please consider claims within 10% of what I measure to be perfectly reasonable (accurate, even).

What’s Included


  • Killzone Flashlights Stainless Steel Pen light (BLF-348)

Package and Manual

The light ships in a thin cardboard box with no labeling at all.


There is no manual.  Aside from knowing if the light will accept 10440 cells (it will) as well as the preferred lower voltage chemistries, there’s not much to know about the light.

Build Quality and Disassembly

The build quality of this light is on par with all the other versions out there.  Probably (possibly) a little better than the SingFire version, and certainly “good enough.”


One thing that always struck me about this light, and the way I actually became accustomed to the term, is how the bezel, body, and tailcap are “match machined.”  That means that after the parts are put together, they’re machined as one (which could be nothing more than a sanding pass), so that all the seams just disappear.


It’s basically just a stainless steel tube!

Here’s the seam for the tailcap.  Opened a bit, of course.  Practically invisible when the parts are snug.


Here are all the parts, aside from a tailcap/switch teardown.  Basically in order, too.  And since it can’t be told from the photo, the o-ring goes above the glass, under the bezel.


The body is just a stainless tube, with a very small shelf for that brass ring that the spring sits on.




These lights are 9cm long and 1.2cm in diameter.  Fairly small lights.

Here’s the Killzone Flashlights pen light beside an official BLF-348.  Identical.  Except of course, for the glow o-ring, I added to the BLF-348.  (It stays put mostly but doesn’t really glow that much.  Micro-review: probably not worth bothering with.)


Not at all the shortest AAA light, however.


A pocket clip is already installed on this light, but very simple to remove.  It’s a friction fit, but slides over the end of the light.  This clip is actually tighter than on my other BLF-348’s, too.


Nothing else is included for carrying this light.

Power and Runtime

The Killzone BLF-348 is powered by an AAA-sized cell.  It’ll accept any variety, too.  Below, have a look at a runtime with an Efest 10440 Li-ion cell.  Note the temperature, too – I had to bump up the scale over on the right side (temperature) for the first time in ages.  With the Li-ion cell, the light gets quite warm!!  The output is appreciably brighter than with any other type cell, though.


But there’s no LVP – so take care of your cells!!

Below is the runtime with an Eneloop AAA NiMH cell.  Output is very stable, until it drifts off because of a lower voltage.


User Interface and Operation

The switch on this AAA light is a reverse clicky mechanical switch.  The button itself is metal, which is great.  There’s a little bit of play in the switch, but not in such a way that the switch gets bound on the way down or up.  Travel is quite long – maybe 1.5-2mm or so.


The button is a little proud, as well.




Mode Mode Claimed Output (lm) Claimed Runtime Measured Lumens
On (10440) 175 165
On (NiMH) 50 50

You may be picking up what I’m putting down in that chart – there’s just one mode with this light.  That mode is “on”.  No moonlight, no turbo, no nothing else.  On, and off.  This is great for some users, not great for others – I like it in this particular light!

LED and Beam

Now the most important part of this light (and exactly why you should go buy one).  This emitter is a Nichia 219b, and it’s what I use as my ‘tint reference’ – so much so that I have a whole section in just about every flashlight review for the last year dedicated to using it as a comparison.


I absolutely love the tint on this light and these emitters.  There’s just a bit of rosy in it, and that’s very much my preference.



LED Color Report (CRI and CCT)

With Eneloop AAA NiMH:

With Efest 10440 Lithium-ion:




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

With Eneloop AAA NiMH:


With Efest 10440 Lithium-ion:


Tint vs BLF-348

On the left is the version, and on the right is my tint-standard BLF-348.  The camera forces a difference like this, subtle as it may be.  In-person they’re not really distinguishable (except that the Killzone is brighter, in this photo).


Random Comparisons and Competitive Options….

Here’s a relevantly filtered page on  Sure there are a number of lights on the list of comparables.  But in reality, this is a bit of a watershed light, and I can’t recommend highly enough that you own one (or many).  Also on the linked list is the Eagtac D25AAA, which I also happen to love, but it’s a twisty with a prominent strobe and is very scarce in the 219b configuration anyway.  So go buy this Killzone BLF-348.


What I like

  • Actual Nichia 219b emitter, with excellent tint
  • Multi-chemistry support
  • Single-mode

What I don’t like

  • Unregulated driver – gets very hot with 10440 cell.
  • No LVP
  • Just one mode


  • This light was provided by for review. I was not paid to write this review.
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