REVIEWER'S NOTE: I am backed up with review samples again, so will only be providing abbreviated comments in this review. All the usual analyses and results are presented, however.
Ultratac is a relatively new maker on the scene. Here, I have their popular initial offering, the 1xAAA K18. Unusually for this class, it features a clicky switch in the head. I have the stainless steel version for review.
Manufacturer Reported Specifications:
Note: as always, these are only what the manufacturer reports. To see my actual testing results, scroll down the review.
- LED: CREE XP-G2 Cool White
- Output/Runtime AAA: Hi: 110 Lumens / 1h, Med: 25 Lumens / 5.7h, Lo: 3 Lumens, 45h
- Output/Runtime 10440: Hi: 360 Lumens / 20min, Med: 80 Lumens / 1.5h, Lo: 5 Lumens, 15h
- 3 Light Levels, Plus Strobe
- Beam Distance: 84m
- Peak Intensity: 1764cd
- Side Button Switch: Provide convenient one-handed operation. No need to twist the head for mode switch.
- Convenient one-handed operation
- Super Long Standby Time: Ultra-low standby current. 80% power 1 year later.
- Compatible with A Variety of Batteries: 1.5V Alkaline AAA, 1.5V Lithium AAA, 1.2V Ni-MH AAA, 3.7V Li-Ion 10440.
- Direct Thermal Patch (DTP) Copper MCPCB: Direct Thermal Path Copper MCPCB provides excellent heat dissipation to ensure the best light performance.
- Reverse polarity protection
- Compact size and light weight
- Body Material: Aluminum, Stainless Steel, or Brass
- Lens: AR coated lens, 99% light transmittance
- Two-Way Clip provides More Carrying Options: UltraTac K18 comes with detachable two-way clip, the flashlight can be put in a purse, pocket, or simply fasten onto your cap.
- Impact Resistance: 1.5m
- Water Resistance: IPX-8, 2m
- Weight: grams 14, oz 0.49
- Length: Inches 3.0, mm 75
- MSRP: ~$22-$30, depending on body material
Again, my review sample is the Stainless Steel version.
From left to right: Eneloop Pro NiMH AAA; Lumintop Tool Ti; Ultratac K18; Lumintop Worm; Fenix LD02; Thrunite Ti3; L3 Illuminations L08.
Ultratac K18 Stainless Steel: Weight: 29.5g, Length 76.0mm, Width 14.0mm (bezel)
Fenix LD02 (with clip): Weight: 16.5g, Length: 76.9mm, Width (bezel): 14.4mm
Fenix E99Ti: Weight: 18.7g, Length: 66.1mm, Width (bezel): 14.1mm
Foursevens Preon P1: Weight 15.3g (with keychain clip), Length 75.6mm, Width 14.0mm (bezel)
L3 Illumination L08: Weight: 22.4g, Length: 77.8mm, Width (bezel): 17.0mm
Lumintop Tool Ti: Weight: 22.6g, Length 73.6mm, Width 14.4mm (bezel)
Lumintop Tool AAA: Weight: 15.3g, Length 82.6mm, Width 14.4mm (bezel)
Lumintop Worm Stainless: Weight: 27.3g, Length 72.0mm (battery installed, off), Width 14.1mm (bezel)
Olight i3 (2013/14): Weight 12.3g, Length: 69.3mm, Width (bezel): 14.0mm
Thrunite Ti3: Weight: 11.5g, Length: 69.9mm, Width (bezel): 13.6mm
Titanium Innovations Illuminati Aluminum: Weight 13.9g (with keychain clip), Length 68.8mm, Width 14.0mm (bezel)
The side switch has a standard feel for an electronic mode-changing switch, and is located under grippy a rubber cover (easy to find by touch alone).
Please see my video overview below for more information about the build.
Press and hold the electronic switch for at least 0.5 secs to activate the light.
Light comes on in its last memorized mode. Click the switch to advance through modes. Mode sequence is Lo > Med > Hi, in a repeating loop. Press and hold the switch for 0.5 secs to turn off the light. Memory for the last mode used is retained.
Double-click the switch from On to active strobe. Single click or press-hold to exit. There is no memory for strobe mode.
Double-click from Off to lock out the light (light will flash once). Double-click again to release the lock out (light with flash twice).
For information on the light, including the build and user interface, please see my video overview:
For all my videos, I recommend you have annotations turned on. I commonly update the commentary with additional information or clarifications before publicly releasing the video.
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The K18 uses pulse width modulation (PWM) at its Lo and Med levels, at a consistent 3kHz frequency:
This PWM is high enough to not be distracting in actual use, although I find it is still detectable at the lowest level (if you are sensitive to it). As usual, there is no PWM on the Hi level.
Strobe is a fairly typical 10 Hz fast strobe.
As on/off and mode switching is controlled by an electronic switch, there is going to be a standby drain.
On my DMM, the current fluctuates initially, but seems to settle down to around 0.14mA. For a 900mA Eneloop Pro, that would translate into just under 9 months before a battery would be fully drained.
It is likely that the electronic lock-out mode would lower this further, but I haven't tested it. The aluminum version should have a physical lock out as well, due to anodized screw threads (not possible on stainless steel)
All lights are on 1xAAA Sanyo Eneloop NiMH, about ~0.75 meter from a white wall (with the camera ~1.25 meters back from the wall). Automatic white balance is set for the Cool White emitters, to minimize tint differences. All beamshots taken immediately upon activation.
All my output numbers are relative for my home-made light box setup, as described on my flashlightreviews.ca website. You can directly compare all my relative output values from different reviews - i.e. an output value of "10" in one graph is the same as "10" in another. All runtimes are done under a cooling fan, except for any extended run Lo/Min modes (i.e. >12 hours) which are done without cooling.
I have devised a method for converting my lightbox relative output values (ROV) to estimated Lumens. See my How to convert Selfbuilt's Lightbox values to Lumens thread for more info.
Throw/Output Summary Chart:
My summary tables are reported in a manner consistent with the ANSI FL-1 standard for flashlight testing. Please see http://www.flashlightreviews.ca/FL1.htm for a discussion, and a description of all the terms used in these tables. Effective July 2012, I have updated all my Peak Intensity/Beam Distance measures with a NIST-certified Extech EA31 lightmeter (orange highlights).
Here is how my lumen estimates compare to the Ultratac specs:
Impressive levels of output on 10440 – and good mode spacing overall, on all batteries.
See my wrap-up section for comments on the runtimes.
The light uses PWM for its Lo/Med level, but at an unobtrusive high frequency of 3kHz.
There is a standby drain due to the electronic switch, which is reasonable at just under 9 months for an Eneloop Pro AAA. Locking out the light electronically should lower this drain and allow a battery to last longer. The stainless steel build tested here cannot be physically locked out, as anodizing is not possible. However, I expect the aluminum build would have this feature.
Tailstanding is not possible.
The K18 is a quality built light, consistent with others I have reviewed in this 1xAAA class. The side-mounted electronic switch is certainly distinctive here – I haven't seen that before.
Physically, this light seems comparable to many others in this class – although I only have the stainless steel version to compare. It is a decent build, with a good range of output levels. I particularly like the Lo to Hi mode sequence, and it does have mode memory.
The electronic side switch worked well in my testing, and is easy to access by touch alone (i.e., it protrudes sufficiently, with a grippy rubber cover). Press-hold for activation makes sense, and I appreciate the electronic lock-out option. I presume the aluminum version can be physically locked out at the head.
Output/runtime performance of the light is very good for this class, on all batteries - despite the use of high-frequency PWM on the Med/Lo levels. Rest assured, the PWM frequency is high enough (3kHz) that it is very hard to detect it visually – and will not be a concern in practice.
I am actually quite impressed with how well it performed on standard alkaline and NiMH rechargeables. Note the L92 lithium performance was not as impressive as some of the competition. But it is a nice touch that 10440 is officially supported in this light – with higher outputs. They have done a good job maintaining reasonable output modes for all battery types.
This is a nice light, with a good implementation of a novel switch position. If you are not a fan of twisy keychain lights, then this is certainly another clicky option. It is also capable of incredibly high output, with the officially supported 10440 option. No issues, the light performed very well in my testing.
K18 provided by Ultratac for review.