JETBeam KO-01 is a tube light with built-in charging.
MANUFACTURER SPECIFICATIONS
Note that KO-01 is currently available under NITEYE brand.
PACKAGING AND ACCESORIES
JETBeam KO-01 comes in a standard cardboard box packaging with all the usual information.
Inside you'll find the flashlight, a JETBeam JL240 2400mAh protected 18650 cell inside it, a Micro-USB charging cable (290mm long), two spare O-rings, a spare switch cover, a warranty card, a manual and a "Certificate of Approval.
The included JL240 18650 has a plastic insert around its contacts to prevent accidental activation in shipping and depleting the cell due to current bleed.
It has over-charge, over-discharge and short circuit protection, 4A maximum current.
I measured it to be 18.5mm in diameter and 68.8mm in length.
In my tests over-discharge protection tripped at 2.5V.
Looks like it's not just a rewrapped cell with a protection circuit added.
GENERAL LOOK AND FEEL
KO-01 is a tube light with an electronic switch on the head, and is on the longer side of the scale.
DQG Tiny III | JETBeam EC-R26 | Olight S20 | Convoy S2+ | JETBeam KO-01 | Fenix E35UE
Anodizing is not the usual black. JETBeam calls it grey, but to my eyes it looks more like what I'd call dark brown. But it's still better than black.
Machining is perfect, I found no sharp corners, chips in anodizing or any other defects in my sample.
Flat cut sides on the head prevent the flashlight from rolling too easily.
HEAD
The bezel is stainless steel and protrudes just a little from the front. It's flat, there are no crenellations.
Lens is ultra-clear mineral glass with anti-reflective coating.
Reflector is smooth and quite deep for the size of the head.
KO-01 uses a cool white XP-L LED. It is perfectly centered using a white plastic centering ring.
Brand and model name are laser engraved on the head, right below the electronic switch.
There is a blue LED behind the switch. It starts blinking slowly when cell charge level is 10%-50% and blinks fast when it's <10%. While charging, the LED is constantly on.
On the other side of the head serial number and hot surface warning are engraved. Below them is a Micro-USB charging port, covered with a rubber flap.
Threads on the head are anodized, allowing for lock-out. There is a spring on the positive terminal, allowing flat top cells to be used.
Unscrewing the bezel was easy, it's not glued. But that's where it got hard. Lens would not fall out, even after repeated and hard smacking. It was flush with the head wall with not enough space to insert something to carefully pry it out. Eventually I decided to risk it and insert a small screwdriver… I chipped the lens, but that made some needed space, and I finally removed it. But reflector still wouldn't fall out, because it was held by an O-ring, hidden in a deep groove. That's what held the lens so tightly.
Reflector is 21.8mm in diameter and 14.5mm in height.
Lens is 22mm in diameter and 2mm thick.
The custom MCPCB is copper.
BODY TUBE
Body tube does not have any markings on it. Knurling is not very aggressive, but not slippery either. Red O-rings stand out.
Threads are trapezoidal cut and anodized. They came pre-lubed and feel smooth in action.
Inner diameter of the tube is 19mm, supplied 18650 fits fine with room to spare.
TAILCAP
Tailcap has straight line pattern knurling.
There are two lanyard holes, so installing a lanyard does not impede tailstand ability. The tail end is flat, so KO-01 can tailstand and is very stable.
The hole in the tailcap is used for installing an optional lanyard ring.
The whole tailcap is anodized allowing for lock-out. Electrical contact with both battery and body tube is made by the spring.
UI
JETBeam KO-01 has four regular modes (Turbo, High, Mid, Low) and one special mode (Strobe). It also has mode memory and will remember last mode used, including Strobe!
One nice feature is smooth ramping between modes. It doesn't instantly go to next brightness mode, but smoothly ramps up (or down) to it.
From off:
I noticed that accessing Strobe from off is more difficult, as if KO-01 would not register sometimes. I tried slow and fast clicking, but couldn't manage to access strobe consistently.
Accessing it from Turbo was very consistent, even when double clicking very slowly.
Mode spacing is not bad, but Low mode is definitely not 1 lumen, it's way higher. Just look at a comparisson with JETBeam EC-R26, which claims 2 lumen:
MEASUREMENTS
Throw was measured with included JL240 cells and HS1010A light meter from distances of 3 and 5m, 30 seconds after start. I got an average of 7340cd or ~171m, which is pretty close to manufacturer spec of 7540cd and 174m.
Standby current is fluctuating rapidly between 85uA and 97uA.
Current draw:
Turbo – 2.8A
High – 1.1A
Mid – 0.39A
Low – 0.07A
CHARGING
Charging is done via a Micro-USB port on the head of the flashlight. Port is covered with a rubber flap.
While the cell is charging, blue indicator LED is on. When the cell is full it turns off.
I discharged the included 2400mAh 18650 cell (to 2.5V, that's when protection trips) and put it on charge in the flashlight. I used Blitzwolf 40W USB charger, which supposedly can give out up to 2.4A, so there shouldn't be any bottlenecks. At the start my USB meter showed 0.82A and charging current slowly dropped throughout the process.
About 5 hours later charging terminated at 0.10A and the cell was at 4.18V.
PWM
I consider myself very sensitive to low frequency PWM and even though KO-01 uses it for High, Mid and Low modes, it's fast enough (18kHz) so that I couldn't detect it with my eyes in normal use.
I consider myself very sensitive to low frequency PWM and spot it easily in normal use, but didn't notice any while using KO-01. A closer look ("wave it around really fast" test) did not show any "trailing" either. Oscilloscope measurements revealed that KO-01 uses PWM at 18kHz for High, Mid and Low modes.
CONCLUSION
KO-01 is a very well built flashlight Smooth ramping is nice, color is not boring black, it tailstands even with a lanyard attached, has a built-in charging and an LED indicator, there's no visible PWM, copper MCPCB is a nice touch. Mode spacing could be better, Low mode is way off spec. Other than that, I'd prefer a warmer tint, different UI and mode order, smaller size (sacrificing lanyard ring attachment point would be the first step in this direction).
JETBeam KO-01 was provided by SkyBen.Trade on Amazon for review.
Thank you for reading.
MANUFACTURER SPECIFICATIONS
Note that KO-01 is currently available under NITEYE brand.
PACKAGING AND ACCESORIES
JETBeam KO-01 comes in a standard cardboard box packaging with all the usual information.
Inside you'll find the flashlight, a JETBeam JL240 2400mAh protected 18650 cell inside it, a Micro-USB charging cable (290mm long), two spare O-rings, a spare switch cover, a warranty card, a manual and a "Certificate of Approval.
The included JL240 18650 has a plastic insert around its contacts to prevent accidental activation in shipping and depleting the cell due to current bleed.
It has over-charge, over-discharge and short circuit protection, 4A maximum current.
I measured it to be 18.5mm in diameter and 68.8mm in length.
In my tests over-discharge protection tripped at 2.5V.
Looks like it's not just a rewrapped cell with a protection circuit added.
GENERAL LOOK AND FEEL
KO-01 is a tube light with an electronic switch on the head, and is on the longer side of the scale.
DQG Tiny III | JETBeam EC-R26 | Olight S20 | Convoy S2+ | JETBeam KO-01 | Fenix E35UE
Anodizing is not the usual black. JETBeam calls it grey, but to my eyes it looks more like what I'd call dark brown. But it's still better than black.
Machining is perfect, I found no sharp corners, chips in anodizing or any other defects in my sample.
Flat cut sides on the head prevent the flashlight from rolling too easily.
HEAD
The bezel is stainless steel and protrudes just a little from the front. It's flat, there are no crenellations.
Lens is ultra-clear mineral glass with anti-reflective coating.
Reflector is smooth and quite deep for the size of the head.
KO-01 uses a cool white XP-L LED. It is perfectly centered using a white plastic centering ring.
Brand and model name are laser engraved on the head, right below the electronic switch.
There is a blue LED behind the switch. It starts blinking slowly when cell charge level is 10%-50% and blinks fast when it's <10%. While charging, the LED is constantly on.
On the other side of the head serial number and hot surface warning are engraved. Below them is a Micro-USB charging port, covered with a rubber flap.
Threads on the head are anodized, allowing for lock-out. There is a spring on the positive terminal, allowing flat top cells to be used.
Unscrewing the bezel was easy, it's not glued. But that's where it got hard. Lens would not fall out, even after repeated and hard smacking. It was flush with the head wall with not enough space to insert something to carefully pry it out. Eventually I decided to risk it and insert a small screwdriver… I chipped the lens, but that made some needed space, and I finally removed it. But reflector still wouldn't fall out, because it was held by an O-ring, hidden in a deep groove. That's what held the lens so tightly.
Reflector is 21.8mm in diameter and 14.5mm in height.
Lens is 22mm in diameter and 2mm thick.
The custom MCPCB is copper.
BODY TUBE
Body tube does not have any markings on it. Knurling is not very aggressive, but not slippery either. Red O-rings stand out.
Threads are trapezoidal cut and anodized. They came pre-lubed and feel smooth in action.
Inner diameter of the tube is 19mm, supplied 18650 fits fine with room to spare.
TAILCAP
Tailcap has straight line pattern knurling.
There are two lanyard holes, so installing a lanyard does not impede tailstand ability. The tail end is flat, so KO-01 can tailstand and is very stable.
The hole in the tailcap is used for installing an optional lanyard ring.
The whole tailcap is anodized allowing for lock-out. Electrical contact with both battery and body tube is made by the spring.
UI
JETBeam KO-01 has four regular modes (Turbo, High, Mid, Low) and one special mode (Strobe). It also has mode memory and will remember last mode used, including Strobe!
One nice feature is smooth ramping between modes. It doesn't instantly go to next brightness mode, but smoothly ramps up (or down) to it.
From off:
- Hold for 0.5 sec to turn on to memorized mode.
- Double click to get to Strobe.
- Hold for 0.5 sec to turn off.
- Click to cycle regular modes (Turbo > High > Mid > Low > Turbo…).
- Double click from any regular mode other than Turbo to get to Turbo.
- Double click from Turbo to get to Strobe.
I noticed that accessing Strobe from off is more difficult, as if KO-01 would not register sometimes. I tried slow and fast clicking, but couldn't manage to access strobe consistently.
Accessing it from Turbo was very consistent, even when double clicking very slowly.
Mode spacing is not bad, but Low mode is definitely not 1 lumen, it's way higher. Just look at a comparisson with JETBeam EC-R26, which claims 2 lumen:
MEASUREMENTS
Throw was measured with included JL240 cells and HS1010A light meter from distances of 3 and 5m, 30 seconds after start. I got an average of 7340cd or ~171m, which is pretty close to manufacturer spec of 7540cd and 174m.
Standby current is fluctuating rapidly between 85uA and 97uA.
Current draw:
Turbo – 2.8A
High – 1.1A
Mid – 0.39A
Low – 0.07A
CHARGING
Charging is done via a Micro-USB port on the head of the flashlight. Port is covered with a rubber flap.
While the cell is charging, blue indicator LED is on. When the cell is full it turns off.
I discharged the included 2400mAh 18650 cell (to 2.5V, that's when protection trips) and put it on charge in the flashlight. I used Blitzwolf 40W USB charger, which supposedly can give out up to 2.4A, so there shouldn't be any bottlenecks. At the start my USB meter showed 0.82A and charging current slowly dropped throughout the process.
About 5 hours later charging terminated at 0.10A and the cell was at 4.18V.
PWM
I consider myself very sensitive to low frequency PWM and even though KO-01 uses it for High, Mid and Low modes, it's fast enough (18kHz) so that I couldn't detect it with my eyes in normal use.
I consider myself very sensitive to low frequency PWM and spot it easily in normal use, but didn't notice any while using KO-01. A closer look ("wave it around really fast" test) did not show any "trailing" either. Oscilloscope measurements revealed that KO-01 uses PWM at 18kHz for High, Mid and Low modes.
CONCLUSION
KO-01 is a very well built flashlight Smooth ramping is nice, color is not boring black, it tailstands even with a lanyard attached, has a built-in charging and an LED indicator, there's no visible PWM, copper MCPCB is a nice touch. Mode spacing could be better, Low mode is way off spec. Other than that, I'd prefer a warmer tint, different UI and mode order, smaller size (sacrificing lanyard ring attachment point would be the first step in this direction).
JETBeam KO-01 was provided by SkyBen.Trade on Amazon for review.
Thank you for reading.
