NWK220 is a second creation of Taiwanese company Niwalker. The first flashlight, they introduced - the NWK750 has been reviewed HERE. Now, I'll take a closer look at the smaller member of NWK family. Just like in case of NWK750, I'm reviewing a prototype. This light is still in testing phase, even official specification hasn't been announced.
Below is specification created by me, on the basis of my observations, measurements and correspondence with manufacturer.
LED: CREE XP-E R3
Brightness: approx 300lm (28,000 lux @1 meter)
Tactical forward clicky tailcap switch and electronic multi-mode tailcap (optional)
Smooth polished reflector, focused beam
Digitally regulated
Working voltage: 3V ~ 9V
Supports 2x CR123A, 2x 16340 (RCR), or 1x 18650
Length: 165mm
Head Diameter: 44mm
Body Diameter: 25mm
Weight: 163g (without batteries)
Made of durable aircraft-grade aluminum
Toughened ultra-clear glass lens
Military spec Hard Anodized, matt black finish
IPX8 Waterproof standard
Rugged construction and reliable electronics
Tailcap lockout
Accesories in retail version: lanyard, spare o-rings, holster, mulit-level tail cap
Niwalker NWK220 is supposed to be a small tactical light with lots of throw. It uses XP-E R3 LED, which is not the brightest nor most efficient LED available, but it has one of the greatest surface brightness. This means, it can throw. And it really can.
The NWK220's look resembles its bigger brother NWK750. The styling is consistent in the NWK series. The head is equipped with fairly substantial crenelated stainless steel bezel and deep smooth reflector. The reflector looks like resized Catapult reflector. The mirror surface finish on it is excellent.
The body has lot of fins and grooves in the head part, the battery tube has circular grooves/ridges. Traditional knurling is used on the tailcap and upper part of the head. One can say, that the "design" is pretty busy. Some may like it, some may not. Personally, I think such aggresive look is OK.
The tailcap has a section that look like anti-roll ring. Unfortunatelly, it doesn't work, it doesn't prevent flashlight from rolling on a oblique surface. The good thing is that the NWK220 can tailstand, yet the access to the forward switch is still easy. The switch itself is similiar to the switch used in NWK750 and other popular tactical lights (Fenix TA/TK series, Eagletac "T" series, etc.) - medium travel and rather on the stiff side. This is not the type of switch (soft with long travel) Jetbeam, Klarus and Nitecore are using in their recent lights.
Machining is on the NWK750 level. It's very well done. All threads are nicely cut (trapezoidal cut). The fitting is tight and the lettering is clear and sharp. Overall finish is similiar to Fenix or EagleTac. The light is not as heavy and rugged as NWK750, but it's not featherweight either. Because my sample is just an engineering prototype, it has some flaws (i.e. excentered bore in battery tube) but retail models will be made with full QC check.
The thread in tailcap is anodised, allowing lockout, the thread in the head is bare, allowing better heat and electrical conduction.
Similiar to NWK750, this model is also designed to use additional electronic switch with modes. I didn't received switch for NWK220, but it's supposed to work exactly as the NWK750's switch. Therefore, I'll paste from NWK750 review the principle of its behaviour. "The switch has two modes + strobe. Within the first five seconds after turn on in works in following sequence (on > hi > lo > strobe >off >on >hi....). After five second since turn on, the circuit doesn't jump to another mode, instead it turns the lights off. The whole concept of additional switch is rather uncommon and I suggested Niwalker, to incorporate modes in the main design in the way Olight and Thrunite works (modes changed by twisting the head) but the guys at Niwalker said that design with additional tailcap is more reliable. I disagree with that, but it's not my project, so I can only post my personal opinion. If you have some other thoughts about it, fell free to post it in the comments."
When using "tactical" switch, the NWK220 is just simple one-mode light. Turn on, turn off and thats all.
There are springs on both ends (tailcap, head), so it can be used on weapon. Springs reduce recoil effect, so they're important in such conditions. The spring in the head allows also for using a flat-top cells.
And a size comparision with other models. From left: Niwalker NWK750, Crelant 7G5, Fenix TA30, Niwalker NWK220, Ultrafire C8, Balder SE-1, Fenix LD01
Circuit, runtime, brightness, etc.
I did some tests with different battery configurations. Niwalker NWK220 isn't driving the XP-E R3 LED very hard. I got the 0.82A reading with 1x18650 cell. Unfortunatelly, I wasn't able to measure current draw on RCR batteries, because the readings I got, were pretty unreal (a quick ramping to 2.0A level). Anyway, the graph will show you what to expect.
Just like in NWK750 the step-down section is a bit inefficient. On two RCRs it should run a little longer than 0h:31min. Fenix TA21 on those AW RCRs runs for 0h:55m in max mode. In 1x18650 configuration the efficiency is very good. The light noticeably dropped in output way after 2h:40m mark.
I did also [lux/1m] measurements. The NWK220 scored 28200 lux/1m (2xRCR configuration), which is outstanding result for a light this size. Just for reference, this is more than Jetbeam BC40 or Fenix TK35. Of course, there's a price user has to pay for such throw. It's the needle-type beam. It's very focused and narrow. As a solace... the corona saves the beam from being unuseful. Nevertheless, I think a little larger-die LED (i.e. XP-G) would be more universal. The throw would drop in the low 20K level, but the beam would be much wider and useful. Manufacturer said, that they're also considering XM-L LED, but this will require a different (stronger) circuit and redesigned reflector. The one used now, is very good for small die LEDs, the beam from XM-L in such reflector, in my opinion, would have too big divergence, still being quite narrow.
Beamshots
OK, now the time for some outdoor shots. Unfortunatelly, currently I don't own any flashlight that is similiar to NWK220 in form factor (only big and small lights in my collection), so I had a big problem with choosing to which other flashlight compare it. The closest with specification and target market is Fenix TA30. It's three years old, uses XR-E Q5 emitter, so it's not a fair comparision, but it's better than nothing.
I would like to notice one other thing. The NWK750 on the shots below looks much, much brighter. Yes, it is, but what you see on the photos, is a bit exagerrated. This is because camera registers light increase in linear function (as opposed to logarythmic function by human eye). If the light is four times brighter, the camera will register it as a four times brighter, for human it will be more or less just twice brighter.
And a short comparision between NWK220 and Jetbeam BC40 (mouse over / mouse out). Both share the same diameter head, but BC40 has shallower and textured reflector. Anyway, this could give you an idea, how would the beam from NWK220 look, if the LED was changed to XM-L. Of course BC40 is driven way harder than NWK220 could be. As far as I know, there's no quality 1x18650 light, that drives XM-L at 3.0A level with flat regulation. The ones based on 8xAMC7135 are linear regulated and in best case, they maintain full brightness for approx. 25 mins (if good, quality cells are used). Again, take into account discrepancy between perceiving different light levels by camera and human eye. In reality, the difference is of course big, but not that huge.
Conclusion
NWK220 is an interesting light. It has a "wow" factor in it - almost 30K lux/1m from pocketable light is indeed impressive. But how useful is it in real life? It'd require some special use to take advantage of such focused beam. For most potential users, I think, the beam from XP-G or XM-L LED would be much more useful. If Niwalker could source the highest XP-G S2 bin, the throw wouldn't suffer much. The additional electronic tailcap with modes, is again, a matter of taste. Personally, I'd like to see modes change by head twisting, separate button or control ring. So the UI aspect is still to discussion. What I liked the most is the overall feel. The flashlight looks good, it's very well made, lays good in hand and throws like no other flashlight in this size class. However it needs some fine tuning. Mostly in electrical (circuit) and optical (LED) departament, because in recent form considering its all limits, it's addressed to a very narrow group of buyers. The MSRP price should be in 90$ range. That's not cheap, but user receives three year warranty and some nice accesories.