Ultratac K18 Mini Brass Keychain Flashlight Review

I, like everyone else, recently reviewed the Ultratac A1.  When I agreed to that one, I also asked for this light, the Ultratac K18 Mini Brass.  Mike at Ultratac agreed, and here’s my review of this tiny little light!

Official Specs and Features


There are three bodies of this light.  Brass (seen here), black anodized aluminum, and stainless steel.
There’s also a 2017 verision, which is an AAA light.


The brass is currently $18.99, and the other two body metals are a dollar more at $19.99.  The 2017 model is strangely $49.99, for no good reason.

Short Review

A clicky on a 10180 light?  Yes please!  In brass!  Even more yes please!  I really enjoy the simplicity of this light, and of course I like brass.  It’s a very nice combo.  I do think brass should always be paired with Nichia, though. 🙂

Long Review

The Big Table

Ultratac K18 Mini Brass
Emitter: Cree XP-G2
Price in USD at publication time: $18.99 on amazon (referral link).
Cell: 1×10180
Switch Type: E-Switch
Quiescent Current (A): ?
On-Board Charging? Yes
Power off Charge Port with no Cell? No
Claimed Lumens (lm) 130
Measured Lumens (at 30s) 125 (96.2% of claim)*
Claimed Throw (m)
Candela (Calculated) in cd (at 30s) 57lux @ 2.849m = 463cd
Throw (Calculated) (m) 43.0
All my Ultratac 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

  • Ultratac K18 Mini Brass Keychain Flashlight
  • 10180 Li-ion cell (not pictured)
  • Charge cap for included cell
  • Charge cable (USB to Micro-USB)
  • Spare o-rings (2)
  • Manual


Package and Manual

There’s a sleeve around a slip-fit box.  The sleeve has instructions printed, and runtimes and the like.

There’s no foam, but the light doesn’t slip around because it’s vacuum sealed.
The vacuum sealed package is intended to protect the brass from tarnishing.  I’m not sure how important that is, because the brass seems to be coated anyway.  There are some finger print marks after use, but it doesn’t have the typical brass smell.
This piece of paper that looks like a manual is in fact not a manual.  The sleeve of the box covers most of the manual type information, except the actual UI.

Build Quality and Disassembly

The build quality of this tiny light is as good as most lights of this size.  Which is to say, acceptable.  Neither bad at all, or greatly fantastic.
There are very light fins in the head, but as cool as this light stays, those are fairly irrelevant.

Below are the contacts of the charging head.  The light head, which I seem to have no photos of, is very similar but with a black mcpcb, and a brass retaining ring.
There’s even a tritium slot in the tail!  It’s a standard tritium slot for flashlights – should fit the ‘standard’ 1.5x6mm tritium vial.


Officially 41 mm long x 13mm head diameter, and weighing in at 17 gram without battery.

This light is small, but there are certainly smaller 10180 lights. I’ll ‘allow’ it because this light is unusually clicky!


The only thing this light includes for carry is the (already installed) split ring on the tail cap.  That’s removable.  The split ring does not prevent tailstanding!


The K18 Mini is powered by a single unprotected 10180 lithium ion cell.  This cell is included.
Here’s a runtime on High.  Thirty second output looks to be around 125 lumens, which is in line with the manufacturer claim of 130 lumens.  There’s no complex circuitry here – output tracks voltage all the way down.  There’s also no low voltage protection.
The K18 Mini (and for that matter, the 2017 edition too) includes a charge port which is screwed on to the body, after the light head has been removed.  Once installed, the included cell may be charged.
It all worked great, and just like it should, but as is the case with all these tiny screw-on chargers, the build quality isn’t fantastic.  See how the port kind of swims in the opening on the charge head.
The charge profile looks great, though.  Stable charging at around 0.11A.  Capacity is around 70mAh, which is typical of these 10180 cells.


User Interface and Operation

In an unusual twist for 10180 lights, this is actually a clicky light!  There’s a side e-switch, labeled “MODE.”  I think the cover is actually metal, and the screen print is just a little off centered on my sample.
The UI is extremely simple.  Here’s a table!

State Action Result
Off Click No action
Off Hold On (Mode Memory)
Off Double Click Switches between lockout (one flash) and Normal operation (two flashes)
On Click Mode advance (L>H)
On Double Click Strobe


Mode Mode Claimed Output (lm) Claimed Runtime Measured Lumens Tailcap Amps
High 130 25m 125 0.26
Low 10 3.8h ~

LED and Beam

Ultratac has put a Cree XP-G2 in this tiny light.  Surprisingly there’s an actual reflector, which is orange peel.  The beam has a good bit of spot, but plenty of spill too, making for a pretty good keychain light profile.

Tint vs BLF-348


Random Comparisons and Competitive Options….

Here’s a relevantly filtered page on parametrek.com. I don’t think you’ll find another clicky 10180 light.  If you don’t care about that, then there are tons of options!  I personally don’t like twisty lights, so this is a great entry for me.


What I like

  • Clicky!
  • Brass adds a nice heft, and the look is great
  • Simple but surprisingly feature rich UI
  • Full package, including cell and charger
  • Charge profile looks perfect
  • Tritium slot

What I don’t like

  • Overall the light could be shorter – a TIR would help with that.
  • I think Brass lights should always have Nichia emitters

Up Next

I have a carbon fiber knife and some other lights for later in the week!  Stay tuned!


  • This light was provided by Ultratac for review. I was not paid to write this review.
  • This content originally appeared at zeroair.org.  Please visit there for the best experience!
  • Whether or not I have a coupon for this light, I do have a bunch of coupons!!  Have a look at my spreadsheet for those coupons. It’s possible to subscribe and get notifications when the sheet is edited!!

Author: zeroair

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