In this Klarus ST10 review I share detailed photos, specifications and why this just might be your new EDC flashlight. Let me just cut to the chase on this flashlight. If you use a flashlight for self defense purposes, the Klarus ST10 has the most debilitating strobe on any flashlight I own. More on the strobe later. Plus, it comes with a rechargeable lithium, is less than $50 AND 1100 lumens. This Klarus ST10 review has plenty of pictures as well (like all of my reviews).
Note: In the interest of full disclosure, the Klarus ST10 used in this review was provided to me by FlashlightZ.com. FlashlightZ.com is a small flashlight company located in Tulsa, OK. You can learn more about them via their social media accounts on Facebook, Instagram, YouTube and Twitter. They also sell their flashlights via Amazon.com as well.
Klarus ST10 Review – Perfect for Everyday Carry
As you can see from the picture below, the ST10 is somewhat between the small and mid-size category of flashlight. When you couple the ST10 size with the 1100 lumens of output you get a super bright flashlight in a compact package. Here is the size/weight info for the Klarus ST10:
- Head dimension: 1.01″
- Body dimension: .94″
- Length: 4.43″
- Weight: 2.08 ounces (without clip and battery)
Klarus ST10 User Interface
I probably can’t call the ST10 a pure tactical flashlight because it lacks a tail switch. All of the modes on the ST10 are accessed via a single side switch. This means you’ll have only one way to hold the light and have access to the flashlight side switch to cycle through the modes. My only minor beef with the side switch is it has a very tiny wiggle as you click through the modes. I’ve heard this comment elsewhere, but my ST10 hasn’t had any switch issues (and neither did the parties mentioning it). It’s a minor nit, but I mention it so you don’t consider it a cause for concern.
You have access to the following lighting modes and run times with the ST10:
- Turbo: 1100 lumens, 1.5 hrs
- High: 400 lumens, 4 hrs
- Medium: 100 lumens, 18 hrs
- Low: 10 lumens, 200 hrs
- Strobe: 1100 lumens, 3 hrs
- SOS: 100 lumens, 54 hrs
With the flashlight off, clicking one time each will cycle the flashlight through low, medium, high and turbo settings. If you are in Turbo mode and click the switch once the flashlight returns to low mode. If you are in ANY output setting – (for example, high mode) and then click and hold the side switch, the flashlight will turn off completely. When you click it again to turn it on it will have the high setting set in memory and always turn on in that mode. Quickly double-clicking the side switch will put the flashlight in strobe mode. To access the SOS mode WHILE IN STROBE MODE, double click the side switch.
Bear in mind that Turbo mode is meant to be used for short amounts of time. The Klarus ST10 has an “Intelligent Temperature Protection System” that will regulate light output when it gets too hot. The purpose of this is to adjust the light output (typically down, not up) should you accidentally leave the flashlight in Turbo mode for an extended length of time. This will help protect the LED and internal components of the flashlight.
Klarus ST10 strobe mode – the best I’ve seen
The Klarus ST10 strobe mode is the most disconcerting strobe effect I’ve had in any flashlight I own. In strobe mode it starts as an intense flicker followed by a slightly lower rate strobe effect and then continually cycles back and forth through these two patterns. I showed this to a friend (who owns many tactical flashlights) and he agreed with me. I think it’s the intensity of the flickering strobe and the cycling between the two strobe patterns that makes it really hard to deal with. Hands down I give it a solid 10 as a self-defensive flashlight.
Klarus ST10 Review – Beamshots
The Klarus ST10 beam pattern is a nice balance. It’s not too narrowly focused (intense pinpointed light but a ton of side fall-off) nor is it too wide and “floody.” It’s a nice combination that yields decent lighting across your entire field of vision, while projecting enough brightness in the center to offer clarity when identifying objects a considerable distance away. The street in the photo below is about 50 – 60 feet away. Note: These photos are straight out of the camera with no editing except cropping.
The woods across the street are about 70 feet away. I’d say at this distance the ST10 in turbo mode is just OK. If you need a flashlight with an extremely narrowly focused beam, you’ll want to consider other models. As a general purpose EDC flashlight I consider the ST10 to be perfectly acceptable.
Here is a good example of the Klarus ST10 beam pattern lighting up an interior stairwell.
Klarus ST10 Review – More about the side switch
Directly in the center of the side switch is a small opaque circle that will change color based on the remaining level of battery power:
- Green – over 70% of battery power remains
- Orange – 30% – 69% of battery power remains
- Red – less than 30% battery power remains
- Red (and flashing) – less than 10% of battery power remains
Note: If you try to charge the flashlight right out of the box it will not work and you’ll see a flashing orange light. That is an indicator to let you know that something is wrong and the flashlight isn’t charging correctly. You’ll need to unscrew the flashlight and remove a small clear plastic piece that is over the battery terminal.
Klarus ST10 Review – Flashlight Specifications
Here is the laundry list of specifications, features, and accessories:
- Extremely long runtime, over 8 days in Low mode.
- Professionally designed optical lens for soft and even illumination without glare.
- Easy to use Micro-USB recharging with protective rubber cover against dust, water and sand
- Intelligent digital recharging module. Real-time progress monitoring to prevent over-charging
- Dual-spring designs for bezel and tail cap to protect against shock, drop, and impact
- Lock-out function specially designed for side-switch UI
- Reverse polarity protection to prevent circuit damage from incorrect battery installation
- Aerospace Aluminum alloy, CNC machining and Mil-spec HA III for anti-abrasion ruggedness
- Features US made CREE XM-L2 U2 LED, up to 50000 hours lifetime
- Working Voltage：2.5V-8.4V
- Battery: 1 x 18650 (protected) or 2 x CR123A
- Reflector: Optical Lens
- Material: 6061-T6 Aerospace Aluminum Alloy
- Accessories Included: 1 x Spare O-Ring, 1 x Lanyard, 1 x Clip, 1 x 18650 Li-ion Battery, 1 x USB Charging Cord
Klarus ST10 Review Conclusion
I hope you found this Klarus ST10 review helpful. As always, here is my PROS and CONS list for this flashlight.
- Nice size for everyday carry
- Good output (1100 lumens) with decently spaced lighting modes
- Best strobe functionality for self defense I’ve seen
- Cheap – under $50 with the rechargeable battery included
- Charge the battery right in the flashlight via micro-usb cable
- Nicely knurled body ensures secure grip in wet conditions
- No tail switch (side switch only)
- Although not a deal killer, I personally would like the flashlight to have a bit more narrowly focused beam
- Switch wiggle – although tiny with no affect to flashlight serviceability it’s still a nit
- BUY IT – size, features and that strobe make it worthy of your EDC rotation
See my other Klarus flashlight reviews here: