Nitecore SRT7i Flashlight Review
The Nitecore SRT7i flashlight is a 21700-cell flashlight using a Luminus SFT-70 for high output as well as great throw. It has USB-C charging, too. Read on!
Official Specs and Features
Here’s a link to the Nitecore SRT7i flashlight product page.
Versions
There’s just one version of the Nitecore SRT7i flashlight.
Price
You can buy the Nitecore SRT7i flashlight right now from nitecorestore.com for the price of $129.95. That includes the very capable cell shown in this test, too.
Short Review
This light really puts out the lumens and the rotary control is very nice. I like that I can essentially leave the light on one output and reliably turn the light on to that mode. USB-C charging works as it should and the included cell seems high quality. Note that to use the built-in charging, you’ll need to use the Nitecore cell (which, again, comes with the light).
Long Review
The Big Table
| Nitecore SRT7i Flashlight | |
|---|---|
| Emitter: | Luminus SFT-70 |
| Price in USD at publication time: | $129.95 at nitecorestore.com |
| Cell: | 1×21700 |
| Runtime Graphs | |
| LVP? | Warning |
| Switch Type: | Dual |
| On-Board Charging? | Yes |
| Charge Port Type: | USB-C |
| Charge Graph | |
| Power off Charge Port | with cell: all modes without cell and/or tailcap: no modes |
| Claimed Lumens (lm) | 3000 |
| Measured Lumens (at 30s) | 2207 (73.6% of claim)^ |
| Candela per Lumen | 32.27 |
| Claimed Throw (m) | 580 |
| Candela (Calculated) in cd (at 30s) | 2090lux @ 6.028m = 75944cd |
| Throw (Calculated) (m) | 551.2 (95% of claim)^ |
| Claimed CCT | – |
| Measured CCT Range (K) | 6000-7100 Kelvin |
| Item provided for review by: | NitecoreStore.com |
| All my Nitecore 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’s Included
- Nitecore SRT7i flashlight
- Nitecore 5000mAh 21700
- Charging cable (USB to USB-C)
- Lanyard
- Pocket clip
- Spare o-ring
- Nylon pouch holster
- Manual etc
Package and Manual
Build Quality and Disassembly
The Nitecore SRT7i is an interesting flashlight. The SRT7i features dual tail switches along with a rotary selector. More on all that later. The build quality here is very good – it’s very “Nitecore.”
Threads on the tailcap are thin (but not “fine”), long, and smooth. They’re anodized, too, but that doesn’t mean you can lock the light out by loosening this tailcap. More on that later, but all the contacts for light output are on the positive end of the cell.
Inside the cell tube on the “positive end” you can see a spring and a metal ring around it. This is positive and negative contact, respectively.
Size and Comps
Length: 163mm
Head diameter: 40mm
Tube diameter: 25.8mm
Tail diameter: 31mm
Weight: 175g (without cell)
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+. Mine is a custom “baked” edition Nichia 219b triple. A very nice 18650 light!
Also above on the left is a new feature light!! Laulima Metal Craft sent this titanium Todai for some size comparison photos like the ones above. Laulima has a bunch of incredible items. I’ve tested one (the Laulima Metal Craft Hoku) (the official site for Hoku is here) that was a Friend Fund Friday review. I was impressed enough by that Hoku that I bought a Laulima Metal Craft Diamond Slim (also in tumbled aluminum) (review is upcoming!) These lights by Laulima have impeccable build quality and not only that, they’re quite configurable. There are some (great, actually) default configurations, but Joshua Dawson (of Laulima Metal Craft) is open to ideas and emitter options and the like. I haven’t reviewed this Todai, but I have to say, it feels absolutely fantastic and I love it thus far. (Notably, I love how warm and eggy those emitters look through the TIR.)
Retention and Carry
Nitecore includes a few options for carry of the SRT7i. First is this pocket clip, which attaches to the body.
This friction-fit pocket clip really only fits on the head end.
The clip has a hole suitable for attaching a lanyard, but better for that purpose are these two loops in the tailcap.
The final way I’d carry the SRT7i is this nylon holster. It’s a very simple holster with a bit of Velcro and a D-ring on the back.
I don’t find the Velcro to line up all that well when the light in placed in the holster.
Power and Runtime
Nitecore includes a single 5000mAh 21700 cell.
The cell is unusual because it has both positive and negative contacts on the positive end. This isn’t really new – Olight has been doing this for a long time. Nitecore has too, for that matter.
One thing Nitecore does that other brands don’t do is on the tail end of the cell. There are both positive and negative terminals here, too!
The cell goes into the light with the positive end toward the head. This is the normal way.
Below are a few runtime graphs. Turbo steps down pretty quickly. For “high” and “medium” I just selected a representative output along the continuum, since the light doesn’t have discreet modes between lowest and highest. I will add, though, that “medium” here is actually specific – it’s where the rotary arrow is aligned with the highest of the little ramp picture. While that’s not a specific claimed output, you could at least approximate a comparison on your own SRT7i if you wanted to do so.
The charging indicator on the side of the head blinks blue quickly when cell voltage is low. The light didn’t seem to shut off, though.
Charging
A USB-C charging port is used for charging. The Nitecore SRT7i flashlight has a sort of novel charge port cover, too. It’s a little hinged cover that really seems to be intended to prevent debris from getting into the charge port. I don’t see in the manual where this USB-C port is stated as being the waterproof variety, but the light itself has IP68 waterproof rating.
The little charging indicator can be seen below – it’s a dot about the USB-C charge port cover. Just like with runtimes, this LED indicates as follows:
Constant on: ≥ 50% power
Slow flash: <50% power
Quick flash: <10% power
Nitecore includes a USB to USB-C cable.
Both C to C and A to C work fine. Charging is quick at around 3 hours.
Modes and Currents
| Mode | Mode Claimed Output (lm) | Claimed Runtime | Measured Lumens |
|---|---|---|---|
| Turbo | 3000 | 3h15m | 2635 (0s) 2207 (30s) |
| Low | 100 | – | – |
| Ultralow | 0.1 | 800h | – |
Pulse Width Modulation
No output was observed to use PWM.
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
The Nitecore SRT7i flashlight has a multitude of operation possibilities. There are two switches on the tail – one is power and one is a “mode” switch, much like a tactical paddle switch.
There’s also a rotary control. The rotary control has multiple states. Below, you can see the rotary set to “locked.”
There’s also a tactical setting.
Here’s a better look at these two switches. They’re both e-switches.
Action is very good for both. The paddle/mode switch has a good bit of texture; it’s very easy to tell the two apart.
Here’s a user interface table!
| State | Action | Result |
|---|---|---|
| Off – Rotary in Lock position | Any | No change in output (still off) |
| Off – Rotary in Stepless position | Click Power switch | On at selector level |
| Off – Rotary in Stepless or TAC position | Tap Power switch | Momentary On at selector level |
| Off – Rotary in Stepless or TAC position | Tap Mode switch | Momentary Turbo |
| Off – Rotary in Stepless position | Click Mode switch | On in Turbo |
| On – Rotary in Stepless position | Click Power switch | Off |
| On – Rotary in Stepless position | Tap Mode switch | Momentary Turbo |
| On – Rotary in Stepless position | Click Mode switch | Strobe |
| Strobe | Click Mode Switch | Return to output level on selector |
| On | Adjust rotary control | Adjust output accordingly |
| Off – Rotary in TAC Position | Click Power switch | Momentary Turbo |
| Off – Rotary in TAC Position | Click Mode switch | Momentary Strobe |
LED and Beam
Nitecore uses a single Luminus SFT-70 emitter in the SRT7i. It’s coupled with a smooth deep reflector.
The bezel has glass breaking balls, too.
LED Color Report (CRI and CCT)
Nitecore doesn’t make a claim of CCT (as far as I see), and I read the light as cool white – from 6000K to around 7100K. CRI is low at around 70, too. Both these facts are typical of this type light and should come as no surprise.
Beamshots
These beamshots always have 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.
I compare everything to the KillzoneFlashlights.com 219b BLF-348 because it’s inexpensive and has the best tint!
Conclusion
What I like
- Good build quality
- C to C charging works very well
- Rotary control is useful
- Dual tail switches are easy to use
- Complete package (comes with 21700)
What I don’t like
- Cool white output
- Proprietary cell is required
Notes
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