Nitecore T4K 4000 Lumen Keychain EDC Flashlight, Super Bright and USB-C Rechargeable with LumenTac Keychain Light

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I didn't notice PWM in the various brightness levels. The distance from the start of the spill to the feet is minimal. DMM: UNI-T UT139C and UNI-T UT210E – 16AWG wire is used directly into the 139C via some banana plugs, and 8AWG wire in a loop for the UNI-T. The DMM I use depends on how high the expected current will be – I use the 139C for <10A, and the 210E for >10A. Olight doesn’t specify the LED used but I measured a colour temperature of a fairly cool 5989K, a very slight green tint and a CRI of 68. The torch I always have on me whatever, is still the RovyVon Aurora A8 I looked at in the keychain torch roundup. Small sample of headtorches I’m testing, ready for next article …

Olight Warrior Mini 3 (new model): UK: https://www.olightstore.uk/s/DS85DL US: https://www.olightstore.com/s/6QEQ5S I also have the SC21 Pro from Sofirn which is very similar but almost half the size and weight, running off a 16340 battery. And it has the option of a higher CRI, warmer LED which I do slightly prefer. The torch has a small OLED screen for real-time display of lumens and runtime. Below the screen are the power and mode buttons. For some reason it arrives in demo mode. Press and hold the power and mode buttons to switch to daily mode. In DEMO mode (default) the light turns off automatically, within 30 seconds, if there is no operation. The countdown will be indicated on the multifunction display. I’ve also measured their colour temperature and accuracy with a spectrometer – if you’re using a torch for longer periods of time the quality of light is also important.Note all beam shots were shot with the exposure fixed and at 5000K colour temperature.

Its output is rather unimpressive though and it’s a little on the large side for an AA or 14500 light. And I can’t help feeling the interface is unnecessarily complex. If Skilhunt could improve the output and perhaps use Anduril 2 firmware instead if they want a customisable torch, I think they could be onto a winner. Thrunite T1S

My first article and video in this series covered even smaller keychain torches. And also introduced a few technical terms – so it’s worth a read / watch if anything I cover in this video needs further explanation.When I saw the size I was skeptical, but this light is awesome. On turbo it's 4k lumens and super bright. I love the button setup too, super simple. I have Olights, and Fenix lights and Weltools. This is my favorite so far... The Nitecore T4K can be turned on and work while charging or remain always on using a USB device such as a power bank (Turbo excluded).

Despite the exaggerated outputs this is a great little torch with bright high CRI LEDs, good build quality and all the flexibility of its Anduril 2 firmware. Fenix E18R V2.0 The Nichia 519A LED sits inside a slightly mottled reflector and there is a noticeable hotspot, but with a fairly low output I still only measured 82 metres of throw with 1682 candela of intensity. Nitecore's T4K Rechargeable Light 4000 Lumens is an impressive flashlight with a number of handy settings. The light output goes from 1 lumen up to 4000 lumens. Admittedly, the 4000 setting can only be used in very short bursts but it is so bright you're unlikely to need it much. The 200 lumen setting is certainly bright enough for most tasks around camp and for general use and the run times for each of the lower settings are impressively long.The Nitecore T4K is a torch designed for versatile and practical use. Its compact size and lightweight construction make it easy to carry and handle. The torch features a maximum output of 4,000 lumens, providing excellent brightness for various outdoor activities and emergencies.

Note: *Turbo mode is a manually operated momentary function and therefore a run-time is not available. With the torch off, by pressing the “MODE” key, the display shows for a few seconds the level and user mode set and the current voltage with the drawing of the battery. Lux Meter: For lumen readings and runtimes, an Adafruit TSL2591 connected to a Raspberry Pi running Ubuntu, using RuTiTe by bmengineer in a custom sphere (build document coming soon, when I have some more time). A UNI-T UT383S is used for candela readings. An Adafruit MCP9808 rounds out the list for temperature monitoring.The Nitecore T4K keyring light has an incredible maximum output of 4000 lumens from the 4 x Cree XP-L2 V6 LEDs and is powered by a built-in, 1000mAh li-ion battery. The flashlight is rechargeable via a USB-C port at the base of the torch and comes with a USB-C to USB charging cable.