[Review} WOWTAC A4 V2

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jeff51's picture
Last seen: 1 day 16 hours ago
Joined: 03/26/2019 - 17:36
Posts: 142
Location: Middle of Texas
[Review} WOWTAC A4 V2

An almost EDC thrower. A coat pocket light that can double as a hand warmer/branding iron.

I got this light on Amazon when it was on sale at the end of Jan 2020 for $39.95.

I’m not providing a link to the WOWTAC page as two different browsers tell me the page is not safe to visit (insert coronavirus joke of choice here).

A friend of mine was looking for a budget thrower and I showed him the WOWTAC A4 (first version) that used 2×18650 cells.
It was a “Shut Up And Take MY Money!” moment.
Unfortunately that version is no longer available.

I saw the WOWTAC A4 V2 and it looked like it was a 26650 version of the first light. And the price was right. So into the shopping cart it went.
When it arrived I found that my assumption was incorrect. The head on the V2 version is nowhere near as large or deep as the first version.

But is it worthy in its own right?
It comes in a cardboard box with a foam cutout for the light.

Included are spare O-rings, extra USB cover (nice), 5000mAh WOWTAC branded battery, Micro USB charging cable, instruction sheet, and the ubiquitous lanyard strap.

125mm (4 15/16”) long
32mm (1 ¼”) wide at the body
48mm (1 7/8”) wide at the head
40mm across the lens (1 9/16”)
34.5mm (1 3/8”) wide at the button area.
It weighs 8.3Oz with the included battery.

The LED is a CREE XHP35 HI. I picked the NW color.

The instructions

Parts is Parts

The head, tube, and cap.

The threads are square cut. Notice the threads on the front of the tube are anodized but the threads at the tail are not. The light is locked out by unscrewing the head.
The threads and O-ring were dry and needed lubing.

The double springs at the tail cap make closing the light a challenge with the included 26650 (“26700”) battery.

You can see the scuff marks on the bottom of the cell from just a few openings.
Most will simply leave the cell in there and use the charger.

A shot of the business end of things

Good thick brass contacts on the PCB.

USB Port is covered.

But It’s not isolated from the insides. The cover comes off easily. Loose the cover and you better stay out of the rain. I’m not a fan of this design.

What’s it like?
It’s nice and compact and fits my hand quite well. I’d call it a coat pocket light. It’s just a little too big for a pants pocket carry.
There is nothing to keep the light from rolling on its merry way when places on anything other than a flat surface. All the roundness makes for a smooth experience – But I wish it has something to keep it from running away.
It tail stands with ease.

Rounding up the unusual suspects
The Sofirn SP36S, WOWTAC A4 V2, WOWTAC A4

And again

More usual suspects.
C8, A4 V2, Refreshing beverage, BLF Q8

The power button is just a hair above being flush with the body.

The button is quite small. It’s a soft translucent material (silicon?) that lets an internal LED shine through.
The power switch LED turns on when the light is on. Except when in firefly mode – then it’s off.
The switch LED is very dim. It is almost invisible in daylight.

The color changes to indicate battery state. Blue for charged, red for low battery.
This doubles as a charge indicator. Red for charging, blue for charged.
It flashes purple to indicate abnormal charging (according to the instructions).

One of the things I do when evaluating a light is to put it on the night stand and use it for a while.
Any idiosyncrasies soon show up.

This is the first light that fails the bare hand test. In the dark it is almost impossible to find the switch by feel. The original A4 had a metal switch that was way easier to find.

This light cries out for an option to have the power button illuminated all the time.

In Firefly it is very usable for dark adjusted eyes. On a floody it would be too bright. On this light the hotspot and spill are so tight it’s easy to keep it pointed away from others.
It would not make a good reading light. Too tight a beam – thinks I.

The UI
The A4 V2 has the standard WOWTAC UI.
From off – Press and hold for Firefly (power LED stays off).
From Firefly – Press and hold to cycle Low, Med, High (Power LED indicates charge).
From off – Click to go to the last mode (L-M-H). It has memory except for Turbo, Firefly, or Strobe.
Double click from any mode to Turbo.
From Turbo – Double click for strobe.
From any mode – Single click for off.

This is a quite usable UI that’s easy to learn and intuitive to grasp just by playing with the light.

The battery measured 3.92V as it came from the box. The battery was locked out by the head being unscrewed.
SanyoGA 18650 vs WOWTAC “26650”

The battery is just a hair over 70mm long. It has a slightly protruding top. I assume there is a protection circuit in there someplace.
I can just manage to get the thing in my LiiKala but it won’t make contact. I’ll need to do some tricks to test it properly.
Other WOWTAC batteries I’ve gotten with lights have all met specs so I believe this one should also.

The extra long battery fills the tube to the brim. As I said the double spring is REALLY tightly compressed when closed on a battery this long.

An unprotected flattop 18650 will work in an adapter tube. A 21700 should work also as the included battery is that same length.

While charging the light using the included cable, I measured just over 2A when using a QC3 USB power source.

When the charge finished, I saw no current being passed to the light.
When the charge completed I measured 4.16V on the battery.
So the charge cutoff seems like it quits at a safe voltage.

My home built lumen box is wildly inaccurate with throwers. Here is what the manufacturer claims.
Firefly – 0.5 Lumens, 208 days
Low – 28 Lumens, 89 Hrs.
Medium – 205 Lumens, 12 Hrs.
High – 1050 Lumens, 8min + 150min
Turbo – 1890 Lumens, 3min + 140min

To me Firefly seems brighter than 0.5 Lumens. It’s so throw(ie) It’s hard to judge.
Medium also seems a bit higher than 200. High seems close. Turbo seems a bit overrated.

On Turbo (cooled with a fan) in RED, High in GREEN

The light holds Turbo well and only dims a bit.
It starts dropping out of turbo at 2m 15s and fully steps down to around a 1000Lm at about 3m 30s
The light quit at: 1H 19m

I gave it a double click after the first stepdown just to see what happens.
It returns to Turbo and then steps down again.
Notice after the stepdown the light gets a bit brighter. I wonder if this is some temperature related function.
The light was close to the 3m stepdown as listed by WOWTAC.
I only got 79m of total run time. WOWTAC lists 143m. I don’t know how much the extra kick into Turbo altered the outcome.

On High (fan started after stepdown (I forgot to turn it on at the start)).
Stepdown starts at 20m 45s and fully steps down at 21m 10s or so
The light starts to dim quickly at about 1h 56m
It turns off just short of 2H.

Once again the light seems well regulated holding high then stepping down. Once again there is the small increase in brightness after the stepdown.
It’s interesting that the specs think high will last 8m before stepdown. That’s not what I observed.
Total run time was not close to the 8m + 150m listed in the specs.
But mine stayed brighter for far longer than the 8m.

Low Voltage
When the battery discharges to a point the light just shuts off.
Notice the slight dimming then nada. Darkness falls.
Pressing the button again gets you zippo. No light at all.

If you break the connection by loosening the head and retightening it the light will function again.
It won’t hold high for any length of time. Low or Medium could be used to “Walk into the light” as it were.

I measured 3.22V on the battery after the light decided to quit. So it seems like WOWTAC wants to protect the cell from deep discharge.

A light is useless if the PWM is nasty. The WOWTAC A4 V2 has none.

On Turbo, Med, Low all I see is a DC offset, with some driver ripple just seen on the trace in Low.

In Firefly mode the scope reveals an interesting waveform. The light is still running a DC offset.
But look at the strange goings on. In my very limited experience with lights – this is new to me.

I thought something was wrong with my test setup. I ran a normal light and got the expected PWM waveform. So it is what it is.
I can’t detect it when using the light.

I was going to include a nifty temperature reading along with the run times, but my thermometer battery died and I didn’t have a replacement on hand.

So I’ll just use the included picture from the ad.

Notice the glove. It should be included in the kit.

Using my moderately calibrated hand – It get’s DAMM HOT!
The whole frigging thing cooks. There is no way anyone is holding onto the head area during a Turbo or High mode run.

What’s it Look Like?
The instructions claim 80K candela with 565m throw.
Comparing it to the original A4 the hotspot is not as sharply defined. I suspect the original version would reach out further.

The NW of the V2 is noticeably warmer than the CW of the original. I like the warmer tint better.

Setting it next to a C8 with the SST40 gives a slightly larger hot spot.

The greater output of the WOWTAC might help it out, but to me the cold C8 looks more “throwy”.
The color temp differences are not as dramatic using mere eyeballs.

Beam Spread
Taking a look at the beam profile

On the rug next to a C8 with SST40. Sofirn SP36S with a wider softer cutoff for comparison.
Not as tight a hotspot as the C8 but has a wider Spill.

Other than the impossible to find in the dark switch, I like the light.
(But you should not need a light to find the switch on your light!)
It could use a better USB port seal and something to stop it rolling away.
A pocket clip that could be positioned next to the switch would solve the rollaway and finding the switch issues.

The “Are you in Turbo or is my hand on fire” mode is something we have to live with in pocket rocket lights.

The WOWTAC A4 V2 is much lighter and easier to carry than the BLF SP36 (3×18650) and has more output than a C8 and has a larger battery.

I really really like the first version of this light with the 2×18650 cells. I wish it was still available with a NW. The long slim tube is very easy to hold and the larger head handles the heat better.
The larger Convoy L6 or the larger still Sofirn SP70 overpower it with simply more light output at the expense of portability.
I’m not sure what role this light fills, but I like it.
But then again I seem to like them all (and therein my problem).

Still on a quest for a budget thower for my buddy. I’m keeping this one.

All the Best,

Swabs's picture
Last seen: 1 day 16 hours ago
Joined: 11/06/2019 - 11:41
Posts: 146
Location: At the tail-end of a torch

Great review!

It is a great little thrower. One of my favorites to EDC. BUT, yes the button is way to small. And, being flush to the body of the torch, makes it that much more annoying. That is my only gripe with it, though.

My Future's So Bright...well, my flashlights are anyways.

jeff51's picture
Last seen: 1 day 16 hours ago
Joined: 03/26/2019 - 17:36
Posts: 142
Location: Middle of Texas

Swabs wrote:
Great review!

It is a great little thrower. One of my favorites to EDC. BUT, yes the button is way to small. And, being flush to the body of the torch, makes it that much more annoying. That is my only gripe with it, though.

Thanks for the kind words,
I managed to get the WOWTAC battery to make contact in my charger.

The 5000mAh cell tested to 5398mAh with a resistance of 28mOhms.
That quite a bit better than the spec.
Even though the tester only can pull .5a.

So the battery isn’t the source of the large discrepancy between the WOWTAC spec run times vs. what I got.

Notice the low resistance. These chargers are not known for great accuracy, but 28mOhms is very low.
It’s as good or better than I get from a Samsung 30Q.
Whenever I test a protected cell, I usually see something in the 85+ range.

The battery is so long that I’m sure there is a protection circuit in there someplace.
I wonder what the deal is?

All the Best,