Thrunite TH20 Pro CW Headlamp Review
The Thrunite TH20 Pro CW headlamp offers reasonable output and good throw with five modes to choose between. It’s a lightweight headlamp that can also use AA!
Official Specs and Features
Here’s a link to the Thrunite TH20 Pro CW headlamp product page.
Versions
There’s just one Thrunite TH20 Pro CW headlamp but Thrunite also sells a neutral white version. I have one of those too; you can see the test results here! If you already read that review, note that this one will be quite similar aside from the data! The lights are the same other than the emitter.
Price
Both versions (including this Thrunite TH20 Pro CW headlamp) sell for $29.95. That includes the 14500 cell seen in this review.
What’s Included
- Thrunite TH20 Pro CW headlamp
- Thrunite 920mAh 14500 (protected, button top)
- Charge cable (USB to USB-C)
- Spare o-rings (2)
- Pocket clip
- Headband
- Manual and papers
Package and Manual
[manual incoming]
Build Quality and Disassembly
Thrunite typically makes a nice quality item, and the Thrunite TH20 Pro CW headlamp is no exception. There’s nothing I would say directly “This should be made better.”
The threads are short and appropriately lubed. They’re square cut and anodized, too – mechanical lockout is possible with just a short twist. One of the ways (I would guess) that Thrunite keeps cost down on this little light is by not including a spring here on the head.
Below you can see the tailcap spring. There’s no magnet under that spring (which I find a bit unusual).
Size and Comps
80mm x 19.5mm x 22mm and 57.6g.
If the flashlight will headstand, I’ll show it here (usually the third photo). If the flashlight will tailstand, I’ll also show that (usually in the fourth photo).
Here’s the test light with the venerable Convoy S2+. The version below is a custom laser-engraved Convoy S2+ host by GadgetConnections.com. I did a full post on an engraved orange host right here! Or just go straight to GadgetConnections.com to buy your Convoy S2+ now!
Also above is the light beside a TorchLAB BOSS 35, an 18350 light. I reviewed the aluminum version of that light in both 35 and 70 formats. I also reviewed that specific edition, the “Oveready BOSS FT Collector Vintage Brass” 35. I love it!
Retention and Carry
The primary means to carry this light will be the headband. On the strap is a nice rubber (silicone?) band. There aren’t any indentions to hold the light, but it’s still held tightly. The strap still allows the light to rotate, too.
The headband is fine. There’s no over-the-top strap, and one is probably not needed for this lightweight headlamp.
A two-way pocket clip is included.
The clip can only attach to the head end, but that still allows for reasonably deep carry.
There’s no magnet! (!!!)
Power and Runtime
A single cell powers the Thrunite TH20 Pro CW headlamp. It’s a button top 920mAh 14500 and is included.
The cell goes into the light in the usual orientation: positive end toward the head.
Below you can see a number of runtimes. This is just testing with the included 14500. The light blinks when cell voltage is low.
The Thrunite TH20 Pro CW headlamp can also run a single AA cell (rechargeable or primary) and has an operating voltage all the way down to 0.9V. I didn’t test any AA cells, but the output would be much lower with that cell!
Charging
While the Thrunite TH20 Pro CW headlamp itself does not have charging, the included 14500 cell does have a USB-C charging port.
A USB to USB-C charging cable is included.
Charging proceeds at around 0.5A when using either A to C or C to C.
Modes and Currents
| Mode | Mode Claimed Output (lm) | Claimed Runtime | Measured Lumens | Tailcap Amps |
|---|---|---|---|---|
| Turbo | 1010-320 | 2m+140m | 672 (0s) 608 (30s) |
2.35 |
| High | 406 | 283m | 294 (0s) 281 (30s) |
0.77 |
| Medium | 120 | 7h | 89 | 0.24 |
| Low | 46 | 16h25m | 33.6 | 0.08 |
| Firefly | 0.57 | 18d | 0.45 | [low] |
Pulse Width Modulation
Every mode except Firefly (left) uses PWM. It’s very fast PWM, though.
Here you can see a “baseline” – a chart with almost no light hitting the sensor. Then there’s the Ultrafire WF-602C flashlight, which has some of the worst PWM I’ve seen. It’s so bad that I used a post about it to explain PWM! Here are multiple timescales (10ms, 5ms, 2ms, 1ms, 0.5ms, 0.2ms) to make comparing this “worst” PWM light to the test light easier. That post also explains why I didn’t test the WF-602C at the usual 50us scale.
User Interface and Operation
There’s a single switch on the Thrunite TH20 Pro CW headlamp. The button has a black look but really seems to be an opaque gray.
Here’s a UI table!
| State | Action | Result |
|---|---|---|
| Off | Click | On (Mode Memory except for Firefly, Turbo, Strobe) |
| Off | Hold 1s | Firefly |
| Firefly | Hold 2s | Lockout |
| Lockout | Click | No Output (switch indicates red) |
| Lockout | Hold 2s | Firefly |
| On | Click | Off |
| On (Except Firefly) | Hold | Mode advance (LMH) |
| Any | Double Click | Turbo |
| Any | Triple Click | Strobe |
LED and Beam
Thrunite doesn’t say what emitter is used here other than saying “High Performance LED.” That’s disappointing but seems to be the way Thrunite is going lately. At least this is neutral white, which is a nice addition to the lineup!
I’ll say that visually the emitter/TIR (what you see above) on the NW and CW versions look about the same. Usually, it’s easy enough to differentiate NW and CW just by how the emitter looks (the output obviously would be different…) but on the Thrunite TH20 Pro headlamp that’s not really the case.
Also interesting is that the NW version is throwier!
Below you can see the NW (left) beside the CW (right.)
LED Color Report (CRI and CCT)
The Thrunite TH20 Pro CW headlamp is in fact CW, coming in above 5700K for all modes. CRI is very low, at around 65, and the Duv is positive. All in all, I might have picked another emitter for this (or maybe both) version of this headlamp.
Beamshots
These beamshots are always with the following settings: f8, ISO100, 0.3s shutter, and manual 5000K exposure. These photos are taken at floor level and the beam hits the ceiling around 9 feet away.
Tint vs BLF-348 (KillzoneFlashlights.com 219b version) (affiliate link)
I keep the test flashlight on the left, and the BLF-348 reference flashlight on the right. These photos are taken around 18 inches from the door.
I compare everything to the KillzoneFlashlights.com 219b BLF-348 because it’s inexpensive and has the best tint!
Summary and Conclusion
The Thrunite TH20 Pro CW headlamp is a great headlamp for $30. I appreciate that Thrunite is offering a neutral white version, but there’s still a good bit of room for improvement. A higher CRI and less green emitter would make this light great! The user interface here is simple and familiar, and I appreciate that the headband is not overcomplicated.
The Big Table
| Thrunite TH20 Pro CW headlamp | |
|---|---|
| Emitter: | “High Performance LED” (Cool White) |
| Price in USD at publication time: | $29.95 |
| Cell: | 1×14500 |
| Runtime Graphs | |
| LVP? | Yes, with warning |
| Switch Type: | E-Switch |
| Quiescent Current (mA): | ? |
| On-Board Charging? | Yes |
| Charge Port Type: | USB-C (on cell) |
| Charge Graph | |
| Power off Charge Port | – |
| Claimed Lumens (lm) | 1010 |
| Measured Lumens (at 30s) | 608 (60.2% of claim)^ |
| Candela per Lumen | 8.27 |
| Claimed Throw (m) | 141 |
| Candela (Calculated) in cd (at 30s) | 286lux @ 4.501m = 5794cd |
| Throw (Calculated) (m) | 152.2 (107.9% of claim)^ |
| Claimed CCT | – |
| Measured CCT Range (K) | 5700-6400 Kelvin |
| Item provided for review by: | Thrunite |
| All my Thrunite reviews! | |
^ Measurement disclaimer: Testing flashlights is my hobby. I use hobbyist-level equipment for testing, including some I made myself. Try not to get buried in the details of manufacturer specifications versus measurements recorded here; A certain amount of difference (say, 10 or 15%) is perfectly reasonable.
What I like
- Low cost
- Nice headband strap (no over-the-top) band
- Familiar user interface
- Includes 14500 cell
- Can run an AA cell too!
What I don’t like
- Low CRI
- Positive Duv
Notes
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