Skilhunt K30-GT (SBT-90, 3x18650) Review: BEAMSHOTS, RUNTIMES, VIDEO and more!


May 27, 2006
Warning: even more pic heavy than usual. :sweat:

I previously reviewed the K30 - a new high-output light from Skilhunt that uses the Luminus SST-90 emitter. In this review, I am looking at the K30-GT ("Great Throw" version), which uses an identical physical build but with the SBT-90 emitter. The SBT-90 has lower overall output than the SST-90, but can be more easily focused for greater throw. :)

Since the physical build of the lights is the same, I will use the same stock body photos from the K30 review – updating where anything changes (e.g., labels, emitters, etc.).

From the K30 review:


And now with the new body label:


Manufacturer Reported Specifications:
(note: as always, these are simply what the manufacturer provides – scroll down to see my actual testing results).

  • Luminus SBT-90 LED
  • Output / Runtime : Turbo 1000lm/1.3hrs, High 570lm/1.6hrs, Med 250lm/4hrs, Low 65lm/19hrs
  • Peak Beam Intensity: 71,500 cd
  • Max Beam Distance/Throw 534m
  • Powered by 3x 18650 (not included)
  • Operating range 9v - 13v
  • Side Switch with Stand-by (blue) and Low Voltage (red) indicator
  • Waterproof standard IPX-6, Impact resistant 1.5m
  • Anti-shattering ultra clear lens, anti-scratching, anti-reflective coated lens with 99% effective transmission
  • Excellent heat dissipation ability, with copper star board
  • Advanced digital power management system
  • One touch battery level with LED
  • 6061# Aluminum
  • Stainless steel bezel and tail rings
  • Color: Black, Hard Anodized finish
  • Integrated power input socket on the tailcap
  • Four indicators on the tail for indicating the batteries condition: (1) 1 indicator on: 20% -40% power remains, (2) 2 indicators on: 40% -60% power remains, (3) 3 indicators on: 60% -80% power remains, (4) 4 indicators on: 80%+ power remains, (5) No indicators on means batteries with less than 20% power remains and need charging
  • Size Length 198.5mm (7.8 in), Diameter Head 76mm (2.99 in) / Body 46mm (1.81 in)
  • Weight 640g (22.58 oz) excluding batteries
  • Notes: Please do not disassemble the sealed part in the head of the flashlight by yourself. Please put the battery's anode side towards the light's head.
  • Limited Warranty From SKILHUNT: Free Repair Service. Cost of parts and shipping fee will be charged. Notify us before return or repair.
  • Package Includes (with Skilhunt Weather-proof storage packaging): Skilhunt Flashlight, AC 100-240v Charger, Spare O-Ring, 550 paracord lanyard, Operation Manual, Warranty Card
  • Optional accessories: 12.6V car charger
  • MSRP: ~$350

Packaging is unchanged from the original K30 – except for this revised sticker on the K30-GT:


Note that the K30 series lights actually come in two types of packaging – a simple cardboard box with packing foam (as shown here), or a plastic carry case with cut-out foam. Either way, included with the light is an extra o-ring, hand-grip lanyard and common manual. The AC charging cable was missing from my K30, but Skilhunt sent me one with the K30-GT (scroll down for pics).




From left to right: AW Protected 18650; Skilhunt K30; Nitecore TM15; Xtar S1; Olight SR95.

All dimensions directly measured, and given with no batteries installed (unless indicated):

Skilhunt K30-GT: Weight: 635.9g (773g with 3x18650), Length: 199m, Width (bezel): 76.0mm
Skilhunt K30: Weight: 636.0g (773g with 3x18650), Length: 199m, Width (bezel): 76.0mm
Eagletac MX25L2:Weight: 468.7g (with battery pack: 744.2g), Length: 266mm, Width (bezel): 62.0mm
Foursevens S18: Weight: 700g (800g with 6xCR123A), Length: 233mm, Width (bezel) 63.0mm
Fenix TK75: Weight: 516.0g (700g with 4x18650), Length: 184mm, Width (bezel): 87.5mm
Nitecore TM15: Weight: 450.6g (634g with 4x18650). Length: 158mm, Width (bezel): 59.5mm
Olight SR95: Weight: 1,224g (with battery pack), Length: 323mm, Width (bezel): 87mm
Sunwayman T60CS: Weight: 338.9g (est 477g with 3x18650), Length: 145.0mm, Width (bezel): 60.0mm
Thrunite TN30: Weight: 468.2g (est 620g with 3x18650), Length: 179mm, Width (bezel): 64.3mm, Width (tailcap): 49.0mm
Xtar S1 Production: Weight: 876.0g (est. 1028g with 3x18650 protected), Length: 240mm, Width (bezel): 83.4mm

Again, the K30-GT build is indistinguishable from the K30 – all that has changed is the emitter. So I will stick with my original K30 pics, except where something has changed.




The K30 series lights are substantial, similar in overall size to the number of the "throwier" multiple-18650 high-output lights. Overall styling is distinctive for Skilhunt though, with some modern-looking touches, like the stainless bezel and tail rings.

Anodizing is a flat black, and seems in excellent shape on my samples. There is no real knurling per se, but there are a lot of ridges to help with overall grip (which I would consider decent). Body labels are fairly minimal, and bright white against the black background. Again, the K30-GT is distinguished only by the revised model label on the head.

The switch design is similar to the earlier Skilhunt lights I reviewed, and features an electronic switch under yellow button with power insignia. There is a clearly audible click upon a press-release of the switch. There are two recessed LEDs on either side of the switch (see User Interface discussion below for an explanation).

The lights can tailstand.

There are series of four contact points in the tail and head of the light, each with its own spring underneath. The included metal battery carrier (which houses 3x18650) fits and should work in either orientation (but see below). The handle screw threads are anodized for lock-out, but because of the tension in the contact springs, you will need to twist the head about a full turn to lock-out the light.

There has been a change in the battery carrier over time, as shown below.

K30 carrier:


K30-GT carrier:


The carriers are basically interchangeable between my two samples – but the new carrier differs physically in that the struts and center column that hold the unit together are thinner now. This allows wider high-capacity cells to be used in the light – I am happy to report that all my cells now fit fine. :)

This new style carrier should be in use on all shipping versions of this light now. One quirk - I found the carrier on my K30-GT would only activate in the light in one orientation. Not sure why, since the older carrier worked fine in either orientation, in either light – Skilhunt will be sending me a replacement new carrier though.

The carriers have slightly raised positive contacts, so flat-top cells can be easily used. Note that I found the clearance of the carriers into the lights rather snug on my samples – thicker high-capacity 18650s in a carrier may have trouble fitting into the handle (i.e., not all of my 2600mAh or 3100mAh cells would fit). :shrug:




The bases of the lights have a series of blue LEDs that read out the charge status of the cells in the carrier (see User Interface for an explanation). There is also a charging port for the supplied cable, under a clear rubber cover. In the center of the tail is the power display toggle switch. Again, see my User Interface and Charging sections for more info.


The charger features a fairly typical transformer brick, rated at 12.6V/1.5A. In my testing, the charger was able to fully charger 3x18650 AW protected 2200mA cells in 2.5 hours. See my Charging section below for a discussion.

You might notice above that Skilhunt send me the standard European plug connector. No problem, as I have travel adaptors for North America. :whistle:

Let's see how the business ends of the lights differ:

K30 head:


K30-GT head:


The most obvious visual difference is that the big round emitter dome is missing on the SBT-90 emitter in the K30-GT. As a result, the SBT-90 die looks smaller than the SST-90 - but I believe this is an optical illusion of the big dome on the SST-90 version (i.e., both emitters feature a die size of 3mm x 3mm). Note that maximum luminous flux of the SBT-90 is considerably lower than the current SST-90s.

FYI, the SBT-90 emitter does have a covering, but it is very thin over the emitter die, resulting in improved light transmission for focusing. So this is different from end-user "de-doming" of the SST-90 (a popular mod here, used to increase throw). But I would expect that the lifespan of a de-domed emitter is presumably considerably reduced (not to mention the risk of catastrophic emitter damage in the attempt). It stands to reason that if Luminus could make a stable SBT-90-style emitter with the higher luminous flux capacity of the SST-90, they would. :whistle:

Both K30 models feature a common relatively large head and reflector, with a stainless steel bezel ring held in place by small recessed hex screws. The emitters were both well centered on my samples. Scroll down for beam pic comparisons.

User Interface

When you first connect the head to the handle/battery tube, a blue LED on the right of the switch will begin flashing once every two seconds. This is to indicate that the light is in Standby mode, and can be activated by a button press. You can turn this indicator off by a quick click from Off (i.e., a press and release of the switch).

To actually turn the light on, you need to press and hold the electronic switch for more than one second. The light comes on in its last memorized level.

To change the mode level when On, do a quick click of the switch. The light will cycle through its output modes in the following order: Lo > Med > Hi > Turbo, in repeating sequence upon clicking of the switch. Note the manual still incorrectly lists the modes in the reverse order.

To access the Strobe modes, double-click the switch from On. Single click to return to the constant output modes. Note that the memory mode will retain Strobe if that is the mode you turn the light off in.

Press and hold the switch for more than one second to turn the light off.

The other LED on the right side of the switch is a red LED that lights up when the batteries are nearly drained. According to the manual, the red LED will come on once the batteries drop below 10V (i.e., below ~3.3V per 18650 cell, which are in series). In my testing, I found the red light start flashing slowly by ~10.7V. Note that if you are running the light on Turbo, this means you will only have a couple of minutes before the cells' protection circuits are tripped, so I recommend you switch down immediately to a lower mode for longer runtime.

On the base of the light, there is a power display switch that lights up the four blue LED indicators on the tail. All four indicators lit up means the batteries are at >80% power remaining. Three indicators mean 60-80% power remains. Two indicators mean 40-60% power remains. One indicator means 20-40% power remains. No indicators mean <20% power remains.

Note that the power indicator lights will activate for several seconds when you first connect the head to the body/battery tube handle. After that, a press of the center switch will perform a battery check. Note as well that the indicator will not give you an accurate power gauge reading if the light is in use (i.e., as with most indicators, the light needs to be off to get an accurate reading).


The K30 series lights come with 12.6V/1.5A charger. I do not know what sort of charging algorithm the light uses. Note that Skilhunt recommends the use of protected 18650 cells in these lights.

When you first connect the charger to AC power, a green LED light comes on the charging brick. Once you connect the charger's DC plug to the back of the light (with battery carrier installed), the transformer's LED turns to red (to let you know charging has commenced).

As a side note, if you plug the charger in shortly after one of cell's protection circuit kicked in to shut down the light, the main LED may turn on upon connection of the charger. This is due to their still being some capacitive charge remaining in the circuit (i.e., it recalls that the light is supposed to be on, once all the cells are back above threshold).

From a fully discharged state, the charging time for my samples was 2 hours and 30 mins for a full charge (i.e., when the transformer brick turned green again). Note the LED indicator turned orange for ~5-10 mins before turning fully green.

In my testing the charger consistently terminated at ~12.59V. That would translate into just under ~4.2V per cell – which is exactly where it should terminate. Of course, if your cells aren't well balanced, you run the risk of over-charging some while under-charging others. In my case, with reasonably well-matched cells, they all came out of the carrier between ~4.17-4.22V – but your experience could be different. That's the challenge with charging cells in series – you are very dependent on their being well-matched at all times. :caution:


For more information on the overall build and user interface of the K30 series, please see my original video overview:

I have updated this information for the K30-GT in its own short video:

Videos were recorded in 720p, but YouTube typically defaults to 360p. Once the video is running, you can click on the configuration settings icon and select the higher 480p to 720p options. You can also run full-screen.

As with 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.


There is no sign of PWM on any level, on either model – I believe the lights are current-controlled. :) Note that this is a departure for Skilhunt – most of their previous lights used visible PWM.

There was some high frequency noise detectable on the Lo, Med, and Hi (but not Turbo) modes of both lights:



This high frequency noise was around ~20 kHz at each level, for both lights. Rest assured, this is not visible by eye – the light is flicker-free at all levels.

K30 Strobe:

K30-GT Strobe:

The K30 series has a fairly typical (and common) strobe mode, of ~9.9 Hz on my two samples.

Standby Drain

Due to the electronic switch, the K30 series will always be drawing a current when the body/carrier is connected to the head. On the K30, I measured this current as 970uA - although it would periodically spike every two seconds to ~2.2mA for a fraction of a second, when the standby flash occurred (if turned on). On the K30-GT, I measured this current at the much higher 4.5mA, spiking to ~5.8mA when the standby flash was in operation.

Assuming you have the default standby flash turned on, that would give you an approximate "average" current of ~1.3 mA for the K30 and ~5.0mA for the K30-GT. Assuming 3x 2600mAh capacity batteries (in series), that would give you just over 83 days on the K30 and 21 days on the K30-GT before fully charged batteries would be completely drained. If you turned off the standby indicator, that would extend your battery life by an extra couple of weeks on the K30, or an extra couple of days on the K30-GT.

As a result, I recommend you store the light with the head fully locked out when not in use. Note that this requires a full turn of the head from the body (due to the springs in the connector).


And now, what you have all been waiting for. ;) All lights are on their standard battery, or AW protected 18650 2200mAh for the multi-18650 lights. Lights are about ~0.75 meter from a white wall (with the camera ~1.25 meters back from the wall). Automatic white balance on the camera, to minimize tint differences.









As always, this beam distance is NOT intended to allow you to draw conclusions on the overall throw. :rolleyes: It is just to provide a standardized distance to allow you compare overall relative beam patterns and intensities.

The K30-GT is clearly not as bright overall as the K30, but it does have greater center-beam throw. Overall beam pattern is not that different, as you would expect given the similarity of emitters and the common reflector.

Unfortunately, we have a lot of snow on the ground here in Canada at the moment (early March). :p So it would not be too easy (or valuable) to try and take outdoor beamshots in my usual location.

In the meantime, here are some indoor shots. These will at least allow you to compare the throw and spill of the three lights. For your reference, the back of the couch is about 7 feet away (~2.3m) from the opening of the light, and the far wall is about 18 feet away (~5.9m). Below I am showing a series of exposures, to allow you to better compare hotspot and spill.





As expected, the SBT-90 in the K30-GT gives you a brighter center beam hotspot over the SST-90 in the K30. Overall output is less on the K30-GT, as shown in the dimmer spill (although spillbeam width is comparable to the K30). The Olight SR95-UT (SBT-90) has an even more focused hotspot and narrower spillbeam (thanks to its larger and deeper reflector, respectively).

By the way, in case you are wondering, here is how the K30 compares to my other two SST-90-based lights – the Olight SR95 and the Eagletac MX25L2:




I will update these comparisons with outdoor shots when available.

Testing Method:

All my output numbers are relative for my home-made light box setup, a la Quickbeam's method. 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 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).


As I pointed out in my earlier K30 review, the SST-90-based K30 has similar overall output to the Foursevens S18 (now called the MMU-HD) or the original Olight SR90, which are both SST-90-based lights. But throw is intermediate between these two, due to the intermediate size reflector.

The K30-GT has considerably greater throw than the K30 version, with a bit of a drop in overall output. Throw is certainly good for the class, as you would expect given the size reflector. I also notice that the measured center beam peak throw of my K30-GT sample is definitely higher than the published Skilhunt specs. :whistle:

Let's see how outputs compare on my two samples, relative to Skilhunt's ANSI FL-1 lumen specs:


As previously noted, my K30 sample is pretty much bang-on with Skilhunt's own specs. But as with my throw measures, my K30-GT seems to consistently exceed the specs for this model. This consistent improved performance makes me think my sample might have a higher output bin than the minimum specs suggest (note that no output bin is given by Skilhunt). But let's see how runtimes do …

Output/Runtime Graphs:



As I previously noted in my K30 review, my runtimes of that model seemed fairly consistent with the K30 specs (noting that my results are based on lower capacity 2200mAh 18650 cells). According to the Skilhunt specs, the K30-GT is supposed to have slightly lower runtime at all levels. But all levels tested, my K30-GT slightly out-lasted my K30. This again suggests that I have a higher output bin in my K30-GT than the minimum specs are built around. :thumbsup:

Otherwise, runtime patterns between the K30 and K30-GT look remarkably similar – just with slightly lower output on the K30-GT. As before, efficiency on Med and Hi modes seems lower than others in the SST-90 class (although I don't have much data on this group to compare). As expected, overall efficiency is typically a bit less than the 3x18650, 3xXM-L lights (i.e., each of those emitters is run at a more efficient lower level for comparable overall output).

Potential Issues

Due to the electronic control switch, the light has a stand-by current when waiting to receive a button press. Skilhunt includes a standby indicator (which can be switched off). I found this drain to be higher on my K30-GT sample, at around ~5mA on average. This would completely drain fully charged cells within a month – so I recommend you break the standby current by a full turn of the head when not in use.

The charger consistently terminated at a reasonable ~12.59V in my testing (i.e., ~4.2V per cell, where it should terminate). But there is no evidence of a charge balancer within the carrier - if your cells aren't well balanced to start with, you run the risk of over-charging some while under-charging others. This is a real concern with any charger that charges cells in series – you are very dependent on their being well-matched at all times.

The original battery carrier fit snugly inside the handle, and not all my 2600mAh or 3100mAh cells would fit (i.e., the cells were too wide). Skilhunt has redesigned the carrier with thinner struts, allowing the use of wider cells now. All my higher capacity cells fit fine inside the light with the new carrier.

Overall efficiency is lower than some of the current-controlled competition, but that may largely be due to the choice of emitter. Regulation pattern is less consistently flat. Note that I detected no sign of PWM or inductor whine on either of my K30 series samples - two aspects that I noted on earlier Skilhunt lights.

Grip is ok, but could be enhanced with some actual knurling.

Preliminary Observations

The K30 and K30-GT differ simply by their choice of emitter – the standard Luminus SST-90 in the K30, and the "throwier" (but lower overall output) SBT-90 in the K30-GT.

As I noted in my earlier K30 review, I am happy to see the continued progression in the circuit design of Skilhunt lights over time. Their early lights suffered from visible PWM and relative low efficiency (plus typically audible inductor whine). I am glad to report the K30 series has no sign of PWM, and no audible whine on either model I tested. :)

In terms of build, the K30 series are physically impressive lights. Grip could be improved with some actual knurling, but otherwise I find the design and ergonomics good. The battery carrier seems solid and well-made (and recently re-designed to allow wider 18650 cells to fit). Skilhunt has always had a flair for distinctive looking designs, and the K30 series continues in that tradition (although perhaps a bit toned down from some of the earlier models). The recessed screws on the stainless steel bezel and tailcap rings are a distinctive touch (i.e., the bezel reminds me of a port-hole on an underwater craft). ;)

Skilhunt has remained with their trademark electronic switch (with yellow button cover) and distinctive user interface - you have to remember to press and hold the switch to turn on/off, and use a single click to change modes. As before, I like the little touches - like the blue standby indicator light that can be toggled on or off, and the battery power indicator on the base. The standby current has increased on my K30-GT sample though, and I find this too high for regular usage (i.e., will completely drain fully charged 18650 cells in under a month). As such, I recommend storing the light lock-out at the head when not in use.

In terms of the beam, the SBT-90 emitter on the K30-GT does indeed produce more center beam throw than the earlier SST-90-based K30. In fact, my direct throw measures were higher than the Skilhunt specs – as were my output readings across the board for the K30-GT (i.e., at all levels). My original K30 was very consistent with Skilhunt's ANSI FL-1 output and beam specs, making me think my K30-GT sample is benefiting from a significantly higher SBT-90 output bin than the minimum specs suggest. This conclusion is supported by the runtime data as well, where my measured performance again exceeded Skilhunt specs. It's rare for me to test a light that exceeds the published specs in every measure. :whistle:

The K30-GT is a nice addition to the Skilhunt K30 family – you get much greater throw, for only a small reduction in overall output (with no real change to runtime or regulation patterns). Design aesthetics are always going to be a matter of personal choice, but there is no denying that Skilhunt continues to push the envelope in this regard. The design and interface of the K30 series is an improvement over earlier Skilhunt circuits.


K30-GT provided by Skilhunt for review.
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May 27, 2006
Thanks holylight.

Just updated the thread - I can confirm that the new carrier allows the use of the wider high-capacity cells now. All my 3100mAh cells fit fine, and Skilhunt informs that that 3400mAh cells worked fine in their testing. :wave: