[Review] - Nitecore Concept 2 - 4x XHP35 HD, 6500lm, 39700cd, 12400mAh - by Lock

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Location: Italia
[Review] - Nitecore Concept 2 - 4x XHP35 HD, 6500lm, 39700cd, 12400mAh - by Lock

Hello everyone, with this review today we will see the Nitecore Concept 2: A powerful light of 6500 lumens in just 11 cm in length. The light was supplied to me by Nitecore specifically for the review.


Packaging and content

The Nitecore Concept 2 arrives in a beautiful and sturdy box of black cardboard. On the front side we there is an elegant silvered lettering and the drawing of the light profile. On the back there are all the main features of the product. The package includes:

  • The light Nitecore C2
  • Laynard
  • Charger
  • Nylon Holster
  • Replacement plug for the micro USB port
  • Replacement rubber for the switch
  • Warranty Card
  • User Manual

Everything is arranged in an orderly manner and well protected by a soft black polyurethane sponge that prevents the light and accessories from moving during transport.

Main features 

  • Futuristic ultra-bright palm-sized flashlight
  • Utilizes 4 CREE XHP35 HD LEDs with a max output of up to 6500 lumens
  • Beam intensity up to 39700cd and beam distance up to 398 meters
  • CNC machined tube features lightweight, solidness and excellent heat dissipation
  • Built-in 12400mAh Li-ion battery with high rate discharge
  • Onboard intelligent charging circuit
  • Crystal coating technology combined with “Precision Digital Optics Technology” for unparalleled reflector performance
  • High efficiency constant circuit provides unwavering output up to 2000 hours
  • Single switch controls 5 brightness levels and 3 special modes
  • Intelligent memory function
  • Integrated power indicator light displays remaining battery power (Patent No. ZL201220057767.4)
  • Power indicator displays battery voltage (accurate to ±0.1V)
  • Advanced Temperature Regulation module
  • Toughened ultra-clear mineral glass with anti-reflective coating
  • Constructed from aero grade aluminum alloy with HAIII military grade hard-anodized finish
  • Waterproof in accordance to IP68 (2m submersible)
  • Impact resistant to 1 meter Manufacturer specifications:

Dimension: 112.5mm×40mm×40mm

Weight: 348g


Output Levels and runtime

The Nitecore Concept 2 has 5 normal levels (including Turbo) + 3 Specials (Strobe / SOS / Beacon) divided as follows:

Turbo: 6500 lm (measured 6564 lm) – 30min

High: 2500 lm (measured 2831 lm)– 1h30min

Mid: 1000 lm (measured 1132 lm) – 6h30min

Low: 285 lm (measured 283 lm) – 16h

Ultra-Low: 1 lm – 160h (measured 1 lm) – 2000h

The special Strobe, SOS and Beacon levels have a declared output of 6500 lm. The data measured by me are to be considered peak (taken within 30 seconds from the ignition and fully charged) and all have proven to be in line with what was declared.

Runtime (first mins) - Turbo Level – home environment 24°C - Uncooling

Runtime - Turbo Level – home environment 24°C - Uncooling

After Power On the brightness decreases very rapidly from the initial 6500 lumens to a very low level around 800 lumens. The temperature obviously grows very quickly and after two / three consecutive activations it is difficult to hold the light in your hands because of the heat produced. Fortunately, the thermal protection system works well and reduces the output if the temperature exceeds the limit threshold. With slight ventilation, after the initial stepdown, the brightness rises to a level of about 1000 lumens. Quite different is the case in which more forceful forced ventilation is adopted. Here are the runtime schemes with a forced ventilation by means of two fans placed in the immediate vicinity of the light.

Runtime (first mins) - Turbo Level – home environment 24°C - Air Cooling

Runtime - Turbo Level – home environment 24°C - Air Cooling

Comparison (first mins) between the Turbo levels with and without forced ventilation

Comparison between the Turbo levels with and without forced ventilation

Runtime (first mins) - High Level – home environment 24°C - Uncooling

Runtime - High Level – home environment 24°C - Uncooling


The body and the materials

As soon as it is taken in hand, the C2 stands out for its small size and for its great compactness. The feeling is to handle a single block of metal. It handles very well and is very portable.

The power button is in a comfortable position, easily detectable even in total darkness or if you are wearing gloves

The weight is abundant, about 350 grams but well distributed. The overall build quality is really excellent. The body made with CNC technology has a good thickness, well done, particularly robust and gives the Concept 2 excellent dissipative capacity.

The bezel of the head and the cap in the tail, are fixed to the body by means of four small screws.

The lens is of good quality and has the classic anti-reflective coating.

Sotto la lente è possibile vedere la reflector e i 4 led XHP35 in versione High Density, quindi non decoupolati, ben centrati ma senza centraled. The reflector is smooth and mirror-polished.

The cap in the tail has 4 tiny screws that, once unscrewed, allow access to the battery compartment. Unscrewing only one of these can also unhook the belt clip. The clip is made of metal, rigid and quite thin and allows you to install the light to your belt very quickly.

The Power of Concept 2 is provided by 4 internal High Drain batteries of 3100mAh each. These are in parallel with each other and make up a 3.7V 12400mAh battery pack that guarantees an excellent runtime even on medium / high levels. To charge the C2 just use the supplied 12V 1000mAh power adapter. A full charge takes about 5 hours. Included in the package is a Nylon holster with a Velcro fastening at the front, and a D-ring at the back. It is well made, rigid and optimally protects the light.

In the four corners of the head there are a series of dissipating fins, deep but relatively small.

The switch is made of rubber with two-stage. Access to its various functions depends on how hard the switch is pressed. A full press is defined as pressing down the switch until a click sound is heard. A half press is defined as pressing down the switch until one feels the resistance but before any click sound is heard.

Under the switch there is a status LED which indicates, by means of a series of flashes, the residual amount of charge with an accuracy of 0.1V.

The lettering is well done and centered. In the tail there is a hole for the laynard

The charging interface is protected by a rubber plug.

Thanks to the flat tail can be used in tailstanding. The anodization is perfect, to the touch it is smooth but not slippery even with wet or damp hands.

User interface

TURN ON: When the light is off, full press the power switch to enter the previously used brightness level.

TURN OFF: When the light is on, full press the power switch to turn off the flashlight.

Changing Brightness

When the light is on, half press the power switch to cycle through “Ultralow-Low-Mid-High- Turbo” mode. The brightness level is memorized. The light enters its previous brightness setting when it is turned back on.

Instant Access to Turbo

  • When the light is off, full press and hold the power switch to instantly access Turbo mode. Release to exit.
  • When the light is on, half press and hold the power switch to access Turbo mode. Release to return to the previously used mode. Accessing Special Mode
  • When the light is on, full press and hold down the power switch until the light enters Strobe mode. After Strobe is turned on, half press the switch repeatedly to cycle through “Beacon-SOS-Strobe”.
  • When the light is on beacon mode, half press and hold down the power switch to directly access Strobe.
  • Turn off the light with a full press to exit the special modes.


With incorporated Advanced Temperature Regulation module, the Concept 2 regulates its outputs and adapts to the ambient environment, maintaining optimal performance.


Lockout mode is designed to prevent light from accidental activation. In lockout mode, the blue indicator under the switch will flash once every time the power button is pressed. However, the light will not emit any beam. It also consumes almost zero power. We recommend setting the light to lockout state when storing it in backpacks or any place that the power button can be accidentally pressed. To enter the lockout, turn off the light first. Half press the power switch for over 2 seconds until the main LED flashes once to notify users that “lockout” has been activated. To exit the lockout, fully press down and hold the power switch for over 2 seconds until the light turns on. The light will resume all functions and return to its previously used mode. NOTE: The light automatically exits the lockout after it is being recharged.

Power Tips

When the light is off, lightly tap the power switch and the blue power indicator underneath the switch will flash to report the current battery voltage (to the nearest ±0.1V). For example, when the battery voltage is at a maximum charge of 4.2V, the power indicator will blink 4 times, followed by a one second pause and 2 more blinks before entering the standby status.


Beam, Tint and Beamshots

The Nitecore Concept 2 beam has a very bright and wide spot. At the same time a bright and usable spill allows you to illuminate well nearby. The tint is Cool tending to the Neutral, i think under 6000k.

The 6500 lumens are real but they are only for a few seconds. After a short time the light becomes very hot and the output goes down quickly.

Beamshot #1

Beamshot #2

Final considerations

Three adjectives are enough to describe Nitecore Concept 2 at best: Quality, Power and Compactness.

The light is really well made, thick materials and finishes with attention to the smallest details.

The C2 is very powerful: 6500 real lumens on the Turbo, even if they can only be used for a few seconds, and over 2500 lumens on the High level. The thermal protection system works perfectly and reduces the output to allow the light to cool and thus avoid potential damage to LEDs and integrated circuits.

The small size and great compactness make this light very portable. The abundant weight, given by the presence of a powerful battery pack, is felt.

The User interface is simple and intuitive, the spacing of the levels is good. Useful the Ultra Low level that guarantees a runtime of 2000 hours with a 1 lumen output.

In short, a small light that, if necessary, turns into a monster!!!

FlashPilot's picture
Last seen: 5 min 48 sec ago
Joined: 05/10/2010 - 16:07
Posts: 4814
Location: USA

Thanks for the review. I wont be buying one because the batteries can’t be swapped out for a fresh set without taking the light apart. Its hard to believe Nitecore crippled such a great light. Maybe a v2 version will come along some time in the future to correct such a huge design blunder.

Last seen: 1 year 4 months ago
Joined: 12/16/2015 - 13:27
Posts: 1640
Location: mod-X

no pix of the battery compartment?

Last seen: 3 days 20 hours ago
Joined: 12/10/2017 - 12:46
Posts: 4341
Location: US

Thanks for the review. For some reason my computer cannot see any of your pics.

Last seen: 10 months 3 weeks ago
Joined: 08/26/2018 - 01:23
Posts: 7
Location: United States

Too bad it’s not designed for user battery swaps. There’s something inherently dangerous about recharging 4 cells in a sealed metal tube… I love the look and woulda insta bought.