Review: Klarus ST11 + CH11 portable charging unit


First post here. 8)
I am a long time reader,but had no enough free time to write.
I have a few flashlight reviews in other forum.I have also some reviews of DIY parts on DX forum.
Now I have a free time and will post my new Klarus ST11 review here.
I put a lot of work and time in it. I hope you like it.
I will add some pictures more especially for BLF._

I am a Klarus fan and their tactical lights are my favorite.
They released new ST models with a design which is more suitable for general use.
I asked Klarus to send me one of these models for review.
And here it is.
These are my impressions and what I think about this flashlight.

First impressions-
-A high quality product
-Nice design,this time not tactical,a little bit heavier than expected-thick aluminum is used here. Looks like from Klarus do not save aluminum.My measurements show that the ST11 draws 2.5Amps from a fully charged battery.So the minimum current to the LED is 2.5A.At this current the XM-L2 led starts to produce a serious heat.So the use of a thick aluminum is justified here.It’s needed for the flashlight to handle all this heat,for extended period of time.

-Excellent dark grey finish with extremely well made knurling and anodizing.Just perfect.
-The knurling is shallower than the previous tactical models.
-Nice anti-roll shape.

Specifications from the manufacturer:

1. CREE XM-L2 LED with a lifespan of up to 50,000 hours
2. Lighting modes: High/Medium/Low/Moonlight/Strobe/SOS
3. Working Voltage: 3.0V-8.4V
4. Battery: 1x 18650 battery
5. Body color: Gun Metal Grey
6. Reflector: Smooth reflector /orange peel
7. Lens: Toughened ultra-clear glass
8. Dimensions: 141mm (Length) x 36mm (Head) x 25.4mm (Body)
9. Net weight: 146g (Excluding battery)

1.CREE XM-L2 LED, delivering a maximum output of 900 ANSI lumens.
2.Patented Tail-cap & Side Switch design, allowing easy access to power settings.
3.Easy-access Strobe feature can activated at any time
4.Ergonomically designed for one-handed operation.
5.Specifically designed tail cap allows upright ‘Candle’ hands-free use.
6.Waterproof design rated to IPX-8 (waterproof to a depth of 2 meters).
7.Stainless Steel bezel design protects the lens and reflector system from drops and impacts.
8.Intelligent control circuits balance brightness, run-time and heat emission for improved performance.
9.Optical lens system allows for illumination up to 100 meters.
10.Anti-shortcut design prevents accidental damage to internal electronics.

ST11 comes in a good simple package.In the box you will find a lanyard,spare O-ring and instructions manual.
No holster included.This time they let us decide what holster to choose.So it’s good idea to ask for a holster when buying.

-It has the most transparent glass I’ve ever seen-I can’t see it is there.Excellent anti-reflective coating.
-I expected to get a flashlight with a smooth reflector…-no I got the OP version.
The reflector is the same size as the XT11 and RS11,but with a little different texture.
-The LED is absolutely perfectly centered.

The screw threads are excellent crafted-anodized,square cut,very smooth screwing.

The side switch is just what it should be.Right size,position and feel.It’s not easy to to find it in full darkness,but you can’t expect to be otherwise from a side switch.

It has a sound tipical for the electronic switches.
I am little surprized,the tail switch has a little louder clicky sound than the XT11’s switch.Maybe this is due to the different mounting position.It is also not so soft on pressing.
On the back you can see the stainless steel ring(it protects the tail from impact) and rotatable lanyard loop.
The stainless steel ring is removable,you can change the switch or the switch cap.

Forward tail switch with momentary ON feature.

Rotatable lanyard loop-Very nice idea.I don’t use a lanyard with flashlights this size,but this is a good option.
It allows the flashlight to stable tail-stands even with attached lanyard.

The battery tube is very well sized.There is enough space even for a big batteries like Sanyo Protected.
I don’t use this battery in Klarus XT11,because its tube is shorter. Here the space is quite enough in length and width and even has a free space.
There is a gold plated spring at both ends.

The pocket clip looks the same used in XT11,so careful with it.Can be attached at the head side,which is a good option. It is very tightly pressed to the body and I think I will remove it in the future.I also don’t use a clip for attaching flashlights this size.

Reverse polarity protection protects the flashlight and battery from damage.

On the front you can see the stainless steel bezel-this time not crenelated.Very stillish and well made.Just the right size.I personally prefer a crenelated bezel because I can see if I forget to turn off the light and leave it on the table.
The smooth bezel is more convenient for general use light and appropriate for carrying in a pocket and is also safer to leave the flashlight in the baggage.

VS Klarus XT11

If you expect a throwy shape beam from ST11,don’t.
It has a similar beam to the XT11 with a difference in the spill,it is brighter,smoother and homogenous.
ST11 is definitely brighter,but you will not see it if you look only the center of the beam.Of course the spot is brighter than the XT11’s spot,but not so much as I expected.The difference is most in the spill-it is very nice smooth and very bright.This is a lot of useful light.To see how much brighter it is,just leave it on a table,tail-standing and you will see that it pumps out a lot of lumens.This is a wall of light.
I found that type of beam very useful once I got used to Klarus XT11.Even the beam is floody,it still has enough throw for an regular use.

The light from the XM-L2 is whiter,no yellowish or greenish tint.It’s better than the light from XP-G2 lights I have.Just perfect for a cool white LED.

From the manufacturer:
Peak beam intensity 7817 Cd
Max beam distance 177 meters

distance= 1 meter 1/20 white wall

Klarus ST11 uses a PWM regulation for changing the different lighting modes.It is quite high frequency 1.56KHz.
There are 4 lighting modes and 2 flashing.High 900Lm-Medium 225Lm-Low 15Lm-Moonlight 1Lm- in that order.
The flashing modes are SOS (with good speed-not too fast) and variable frequency strobe.
“Note: All specification data was achieved using 18650/2200mAh/4.2V batteries.” -I find this in the specifications.

The PWM is not detectable on High brightness mode,on medium and low can be detected with a cooling fan.On moonlight is easy detectable.
Something very interesting and important in this model.As many other lights it makes a step down in the brightness after a few minutes in High mode.
I waited to see it a few times,with no result.After a few tests I found that the driver starts to change very slowly a PWM signal to the LED at the 4th minute and stops at the 5th. This means that ST11 makes a brightness step down in a minute and is impossible to see this step.Well done

UI-from manufacturer
A Tail Power Switch:
1.While OFF: Lightly depress switch to activate momentary-ON
2.While OFF: Fully depress switch fully for constant-ON
3.While ON: Fully depress switch for OFF.
Other functions please reference to B, C.

B Side Switch
1.While OFF: Short press (< 1 seconds) to activate momentary-ON
2.While OFF: Long press (> 1 seconds) to activate constant-ON
3.While ON: Long press (> 1 seconds) to change MODE.(High/Med/Low/Moonlight)
4.While ON: Short press (< 1 seconds) for STANDBY.
5.From ANY mode: Fast double-press to activate STROBE. Press the switch again to turn STROBE off. (The Tail Power Switch MUST be turned ON)
6.From STROBE mode: Long press (> 1 seconds) for SOS.

C Memory function:
When a lighting mode is on for more than 3 seconds, the mode will be memorized. The device will return to this mode when turned on next.

Off/Standby function:
The Tail Power Switch will completely power-down the torch when turned OFF, preventing accidental activation of the side switch whilst the torch is in storage or being carried in a pouch.

My thoughts:
Can be used as a single mode flashlight.Just leave it on the mode you want to use for 3sec,then turn it off with any of the switches.After that every time when you press ON the tail switch it will come on the mode you chose.The tail switch can’t change the brightness mode.This way you have a single mode flashlight with momentary on function.Great

Fast double press activates variable frequency strobe.It alternates 17 Hz and 7 Hz.
From strobe-long press activates SOS.

Beamshot comparison
Distance 5 meters 1/6 sec , f3.4 WB and focus locked
Klarus ST11 High - Medium - Low

Klarus RS11, Klarus XT11, C8 XM-L T6, C8 XP-G2, 52mm SMO XM-L T6, 26mm SMO XP-G R5

1/50 sec , f 3.4 WB and focus locked
Klarus ST11, Klarus RS11, Klarus XT11, C8 XM-L T6, C8 XP-G2, 52mm SMO XM-L T6, 26mm SMO XP-G R5

Klarus ST11, Klarus RS11, Klarus XT11, XTAR B20, C8 XM-L T6, C8 XP-G2, 52mm SMO XM-L T6, 26mm XP-G R5, 26mm XR-E Q5, Klarus RS16
Distance 40m 3.2 sec ,f 3.4 , ISO 80 , WB and focus locked

Animation- ST11, XT11, RS11, XTAR B20, C8 XML, C8 XPG2, 52mmSMO XML, 26mm XPG, 26mm XRE Q5, Klarus RS16


Good grip. The thicker part at the tail helps for that.

CH11 charger-Optional

Unique feature for ST11 and STC2. Portable charging unit. Screw on instead of the head and plug the supplied cable to USB or 5V AC adapter.
Well packed in plastic case. Included -charging cable USB>MicroUSB, 31cm/12.2 Inch lenght, instructions manual.

The supplied cable is long 31cm/12.2 Inch,good for charging from laptop.
I usually charge with 1m/~40 Inch Micro USB cable for Nokia cellphone.

1. Easy-carry screw-on charger for ST11 Torches
2. Compact and Lightweight design (just 16.8g)
3. Used for in-torch recharging of Li-Ion batteries
4. Reverse polarity protection
5. Micro-USB to standard USB cable supplied
6. Can be used off any USB port (5V/500MA output required)
7. Features three charging modes (CC, CV and Trickle Charge)
8. Automatically stops charging when complete (4.2V cut-off)
9. Charging Indicator lights for easy reference (red and green light)
More info can be found at the Klarus website.

After about 10 times charging,I can say-this is the best charger I own. Never exceeds 4.2 volts. And even better-I left a Sanyo 2600 protected battery in it after charging complete at 4.197V,for 2 more hours and the voltage was still 4.197V. This is just great for such a small charger.
There are three charging indicator modes.
Green with blinking Red-the tail switch is OFF-It should be ON to make connection to the negative battery contact.
Red light-Charging
Green light-Complete
One recommendation from me-When the charging is complete,turn OFF the tail switch,because when you screw on the flashlight head and the switch is turned ON,the light will start automatically on the last used brightness level.

Thanks for reading!

Special thanks to Klaruslight for providing ST11 for Review!

Nice review, thanks! Welcome to BLF too!


Thanks Garry

Sweet review Thanks for sharing! The picture that spins the light in a circle and does various stuff was super nice! :wink:
Welcome to BLF! :party:

Thank you!
Glad you like it.
Review is now updated with two videos.
Check them out. 8)

Are you kidding?! Your first post and you hit us with one of the best reviews I’ve ever read!!! You’ve set the bar high my friend!!


Thank you! :slight_smile:
I have new lights for review,so next weeks I will post more good reviews like this.

Fantastic review !

Great pictures , comparisons , and comprehensive narration .

Well done . Thank you .

Nice review. Thanks

Thank you leaftye !

Thank you!
I can write even more,but my English is not good enough.

In my opinion, THAT was one of the best reviews I have ever seen/read. Incredible photographs (what camera?) And yes, that 360 degree thing is too cool. The review was so nice I don’t remember what flashlight was reviewed “:o) VERY WELL DONE!

My last post was too short for justice. The creativity and information provided in this review is what I'd only expect from someone that's truly into flashlights and has done LOTS of reviews. My own reviews might never be this good.

Very nice review. The info is well spaced throughout and keeps the whole thing fresh. Thanks!.

what a first post! welcome and thank you for the review.
job well done

Thank you all 8)
My reviews contains the best of my hobbies-flashlights and photography.
I am trying to improve the quality of each new review I make.
I like to show high quality pictures in my reviews to show the real shape of the flashlight.
If you like macro videos of flashlights,check out my youtube channel,because I have no time to post my previous reviews here.
I am happy when people enjoy my review even they are not interested in the flashlight.
Thank you for your comments!

Thanks a lot for the review! Frontpage’d and Sticky’d.

Just saw this… nice review!

Can you comment on the water-resistance (?water-proofness?) of the CH-11 charging unit when it’s installed?

CH-11 has two holes for the charging status and they are not sealed.The micro USB port is also not sealed,so it’s not water resistant.

Thanks for the info — much appreciated.

Great review FlashLion.
This thread actually pushed me to get one for myself (ST11). Been using it as my main EDC for several weeks now. Looks great (“pogi” in local lingo). I find the size is just right for me. The moonlight mode is very handy and its the most used mode. I actually use it more than my smaller Quark Pro QPA and LD10.

Will be going a short island vacation this Sunday and will surely have fun using it.