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Wurkkos WK02 Review: Penlight flashlight
Wurkkos WK02 specifications
|LED||Luminus SST20 (4000K)|
|Max. Lumens||300 lm|
|Max. Beam intensity / distance||1165 cd / 68 meters|
|Review date||February 2022|
Just when I started this review I saw a message from Wurkkos saying the WK01 and WK02 are going to be discontinued. It’s possible to get the light at some stores with stock, but Wurkkos will no longer make them. So far for that.
Since we are reviewing penlights, I looked around and found the Wurkkos WK02 penlight with a high CRI LED. (Luminus SST20 4000K). And Wurkkos was kind enough to send me one.
From this price point, you don’t really have to worry about the packaging. It’s a simple white and orange carton box with the light inside, packed in bubble wrap. The box contains the following:
- The flashlight: Wurkkos WK02
- 2 spare o-rings
Flashlight in use
The WK02 has a forward clicky switch, that feels a little mushy. There is some play between the rubber boot and the switch. So you can move the rubber boot around (because it sticks out) without activating the light.
When you press the switch straight from the top, it feels like any other switch, and works fine.
And because it’s a forward clicky switch, you’d have to tap 2 times for medium mode, and 3 times for high mode.
The pocket clip is silver, and very very stiff. It’s a little too stiff to comfortable clip it to the pockt of a shirt. And it’s also very hard to remove without the use of a tool. It can be moved position in its slot, but it’s one of the stiffest pocket clips on all the penlights I have tested. But there is still 1 positive thing to mention about this clip though: it’s working wonders as a anti-roll feature.
Build Quality, and Warranty
When it comes to the anodization, it’s totally fine for it’s price, but not as good looking as some premium flashlights. But for the price, you can’t complain. It’s black and a little bit shiny.
One thing that I also noticed is the knurling near the tail of the light. Just below and above the place to attach the pocket clip. But there is no tailcap, because you have to insert batteries from the front. It’s only the head that can be removed. So the knurling does help to unscrew the head, but it’s not used to unscrew the tail.
The threads are shin, a little sharp, and anodized. So practically speaking, you can use the WK02 as a twisty. Just activate the switch, and use the head to turn the light on, off, and change modes by screwing and unscrewing it.
Warranty: The manual states “Please contact us if you have any questions. If your product is defective please contact us for refund or replacement within warranty period.” But it doesn’t state how long that warranty period is.
LED, Lens, Bezel, Beam, and Reflector
One of the reasons why I wanted to test the WK02 is the LED it’s using. It’s a Luminus SST20 with a color temperature of 4000K, and it’s supposed to have a CRI of 95.
The LED sits in a shallow, smooth reflector, protected by a coated glass lens. Most coated lenses have a purple-ish coating, but this one looks blue. That’s a little uncommon.
Using the Opple Light Master 3, I got the following readings. (I measured low and high. High at a distance of 60cm, and low at a distance of 2 cm, pointing directly at the sensor)
- CCT: 3604K-3701K
- CRI (Ra): 96.0-96.1
- DUV: -0.0002 on Low and 0.0017 on high.
Dimensions and size comparison
- Length: 128.7 mm / 5.07 ”
- Head diameter: 13.98 mm / 0.55 ”
- Tailcap diameter at knurling: 14.05 mm / 0.55 ”
- Empty: 20.2 g / 0.71 oz
- With battery: 43.9 g / 1.55 oz
Size compared to other popular penlight flashlights
Driver & User Interface:
The WK02 has 3 modes, without any hidden ones like strobe. And because it’s using a forward clicky switch, without mode memory, you have to tap the switch 2 times for medium, and 3 times for high. You can’t change modes when the flashlight is turned on.
- Low, Medium, High
- Half-press: momentary on
- Half-presses: change modes
- Single-click: turn on
- Single-click: off
- Always start in low
- No, so it always starts in low
Blinky modes menu:
Low battery warning:
- No, so be careful using 2*NiMH batteries!
- No, and not necessary with this type of mechanical switch. You can also unscrew the head just slightly to break any electric connectivity
- Not visible by eye in any mode.
Batteries & Charging
Wurkkos didn’t include batteries, and I don’t blame them for it. Other brands send Alkaline batteries along with the light, and that’s quite brave because Alkaline batteries can leak and destroy the flashlight.
For testing, I used 2 AAA Eneloop standard batteries with 750mAh capacity. These are very robust and can take a beating. They are rechargeable and have a low self-discharge, so you can get the best of both worlds.
Keep in mind though, that the WK02 doesn’t have low voltage protection, and this will result in deeply discharged batteries if you don’t keep an eye on the flashlight. Rechargeable batteries don’t like a too deep discharge too much!
I normally recommend against using Alkalines, but in some cases, I can understand using them, and this is one of those cases. But note, you should only use them if you use the flashlight on a daily or a very frequent basis. If you use the penlight only once in a few months, don’t use Alkaline batteries!
Oh, and don’t use 2*10440 batteries!
All output numbers are relative to my homemade Integrating Sphere. It is set up with an Extech SDL400 Lux Meter for measurements including a Kenko PRO1D ND-16 filter. The base measurement is done with a Convoy S2+ that has been tested at 255 lumens.
For Amp readings, I use a Fluke 77III DMM. For higher amps I now use a Fluke 325 True RMS clamp meter. For microamps, I use a cheap DMM with an easy-to-use micro amp setting.
All of my readings were taken from fully-charged Panasonic Eneloop AAA batteries.
|Mode||Specs||@ start||@ 30 sec||@ 10 minutes|
It didn’t come close to the advertised 300 lumens, but the specs probably were for the 6500K version. There is only 1 sheet with specifications, while there are 2 types of LED for the WK02.
The runtime test was done with the 50cm integrating sphere, including the Kenko Pro1D ND-16 filter and Extech SDL400 data logging Lux Meter.
No low voltage protection, and flashlight started to flicker on high mode, when the batteries ran low.
High mode started at roughly 195 lumens, and slowly decreased, but maintained the output pretty well for the first 36 minutes. At that point, the last measured output was 182 lumens before it dropped. You can see the blue line dropping rapidly, and the slowing down a bit. At 42minutes it reached 20 lumens, and that’s about 10% of the initial output. At 1h05min the output was down to 1 lumen. Not long after the light started to flicker.
Medium mode started at 82 lumens and slowly dropped to 52 lumens in 10 minutes. It continued at that output for 3h58min when it quickly dropped. At 4h09min it was 8 lumen (end of runtime) and reached 1 lumen at 4h41min.
Low was about 1.4lumen for 45h22min when it slowly decreased. At 47h13min the output was down to 0.1 lumen.
Measurements were taken both indoors at 2meters with a professional Hagner E4-X Lux Meter.
|high||1,165 cd||1,168 cd||68||75|
Those were just spot on!
For the following beamshots I used a Canon EOS 5D Mk2 and a 50mm lens. manual settings: ISO1600, 1/30sec , F4, 5000K
The white wall is about 5 meters away, and the fence about 4.
Disclaimer: This flashlight was sent to me for review at no cost by Wurkkos. I have not been paid to review, nor have I been holding back on problems or defects.
- Affordable at $20
- Plenty bright, and sustains output for 30 min on high
- No PWM
- 3 modes
- No mode memory
- High CRI
- 47 hours runtime on low
- Not reaching claimed 300 lumen output
- Pocket clip is very stiff
- Rubber switch boot feels a bit mushy
Explanation on star ratings:
1: Avoid: my phone flashlight would be a better choice – 2: Poor: significant defect or issues; almost unusable – 3: Average: some defects or issues; but still usable 4: Good: recommended (minor issues) – 5: Great: highly recommended
4 stars: ★★★★
To me, it feels like penlights are used for a very specific reason, unlike EDC flashlights. But if you’re looking for an affordable penlight, with 3 modes, always starting on low, and high CRI, better get one, before it’s discontinued. It’s currently only $9