The flashlight was sent to me by Cyansky for review.
Here's the product's link: Cyansky K3
The flashlight comes in a nice cardboard box.
Here's a closer look at the manufacturer's specifications.
The following accessories are included in the box:
- Cyansky branded 21700 battery
- Wrist lanyard (with some nice braiding!)
- 1 x replacement tailcap boot
- 2 x replacement o-rings
- Pocket clip
- USB Type-C charging cable
- Carrying pouch
- User manual.
The carrying pouch is made out of nylon.
The overlapping flap is secured in place via velcro, while a belt loop is present in the rear.
The Cyansky K3 comes with a black matte anodization.
The overall fit and finish is excellent.
Its body comes with parallel knurling for better grip.
The flashlight is dual switch operated.
The rear mounted, forward clicky switch is used solely for controlling the power on/off of the flashlight.
An e-switch mounted in the lower part of the head is responsible for controlling the mode switching.
The switch is made out of sandblasted metal and sits also flush with the surface of the flashlight.
A mildly crenulated bezel is in place to protect the glass lens.
Its worth noting that the bezel and head is a unibody piece.
Looking down the head, we can see a smooth reflector along with a Luminus SFT-40-W.
The centering of the emitter is perfect.
The driver seems press fit and glued.
A brass tab is used as the positive terminal in order to ensure maximum efficiency
The rear switch boot sits below the two metal flaps, which allows the flashlight to tail stand.
The tail houses a copper spring.
The spring board is held in place via a retainer ring.
Here's the tail all taken apart.
And a close up shot of the forward clicky switch.
Both the front and rear threads are square cut and are anodized, which allows the flashlight to get mechanically locked out.
A detachable pocket clip is also included.
The clip is quite stiff and provides excellent retention.
As already said, the Cyansky K3 comes with a 21700 battery.
The battery also includes a regular USB Type-C charging interface.
Once plugged in, a little indicator LED will shine up inform the user about the charge's state
green: full, red: charging.
User Interface
Being a tactical flashlight, the Cyansky K3 comes with a simple and forward UI.
Here's all the actions supported by the flashlight's firmware:
Turn on/off: Single press (rear switch).
Mode cycle: Single press (side switch) ( Low > Mid > High > Turbo > Low > ...)
Strobe: Long press (side switch)
Mode memory is present.
Low Voltage Warning and Low Voltage Protection is also present. The flashlight will flash 3 times whenever the battery gets low. I measured the cutoff voltage at 2.8V
Output
Here's my output measurements along with the respective current craw per each output level.
The Cyansky K3 push more than 1500 lumens at Turbo.
The manufacturer's specifications seem to be pretty accurate.
Mode spacing is excellent!
Power Regulation
Here's a power regulation graph that I've created for the K3.
What we can see in the graph:
- Turbo's current draw is proportionate to the input voltage
- High is fully regulated up down to 3.3V
- Medium and Low are fully regulated for the whole span of the battery's voltage.
- Turbo and High will stepdown to Medium once the battery's voltage < 3.3V
- Medium will stepdown to Low once the battery's voltage < 3.1V
Outdoor beamshots
And here's a few outdoor beamshots.
Bottom Line
The Cyansky K3 is a great tactical flashlight.
Its driver shows signs of great regulation and its Luminus SFT-40-W emitter is basically a dedomed SST40 and is great at producing a good balance between throw and output!