In my review of the Nitecore EX7, I was impressed by the innovative M515S LEDs, but deeply disappointed by the operation of the flashlight. About nine months later, Nitecore has now presented the P27iX as the solution to this problem.
The Nitecore P27iX is designed as a tactical flashlight and features three buttons for intuitive operation and direct access to up to five brightness levels. This model also offers a kind of zoom function thanks to its special LEDs, allowing the width of the light beam to be adjusted.
You can find the German version of this review on my website: SammysHP Blog › Nitecore P27iX
The flashlight was provided by the manufacturer for this review. Thank you very much!
Hardware
The flashlight comes with accessories in a black-and-yellow retail package. The contents are organized into two compartments, with the flashlight itself held securely in place by a vacuum-formed insert.
- Nitecore “NL2155HPi” 21700 Li-ion battery (5500 mAh, 3.82 V at arrival)
- Dual-way clip
- Combined lanyard and charging cable
- Replacement O-ring (1×)
- Adapter for two CR123A batteries
- Belt holster
- Quick start guide, manual (EN, ES, DE, FR, RU, IT, UK, PL, EL, CN)
In addition to the detailed user manual in ten languages, there is also a quick start guide that summarizes the most important operating information in the form of easy to understand diagrams.
In my view, the P27iX represents an evolution of the Nitecore EX7, which is why I would like to briefly compare the two models here side by side. While there are also differences in performance, the most important factor for me is the significantly improved user interface of the P27iX.
The P27iX is slightly slimmer overall, but a little longer than the EX7 due to the switches on the tailcap. In terms of weight, the two models are very similar, both coming in at just over 200 g, which is a reasonable weight for a flashlight of this type.
Length: 141 mm
Diameter (head): 31.9 – 35.9 mm
Diameter (battery tube): 26.0 mm
Diameter (tailcap): 28.3 – 32.6 mm
Weight (without battery): 128 g
Weight (21700 battery): 77 g
Weight (total): 205 g
When compared directly with other tactical flashlights powered by a 21700 battery, it becomes apparent just how compact the P27iX really is. Yes, there are more compact 21700 flashlights, but those tend to fall more into the EDC category and are less focused on tactical requirements. An even smaller flashlight would actually have a negative impact on handling, especially when wearing gloves.
Klarus XT21X Pro | Armytek Predator Pro Max | Nitecore P27iX | Nitecore EX7 | Nextorch TA30C Max
At first glance, the P27iX immediately stands out with its distinctly tactical appearance. While there is a certain degree of elegance to its design, the primary focus is clearly on ergonomics and durability. The body is made of aluminum and is available exclusively in black.
The bezel is made of black-coated stainless steel to better protect the flashlight in the event of a fall. Thanks to its crenelated profile, it is also possible to tell whether the flashlight is turned on when it is standing on its head. Three embedded silicon nitride balls allow the flashlight to be used as a glass breaker. However, these also make the flashlight somewhat unstable when standing on its head.
On the side of the head, the SET button and status indicators for brightness and battery level can be seen, which I will go into in more detail later in the “Operation” section. The beveled ring reliably prevents the flashlight from rolling away.
The coarse texture of the battery tube provides excellent grip even in wet conditions. The trapezoidal rings are intersected by spiral grooves. The surface is clearly noticeable in your hand, but it has no sharp edges or pointed corners.
The tailcap is not rotationally symmetrical. With cylindrical flashlights, this is rather unusual, since the threads usually require considerable effort to manufacture in a way that ensures all parts are precisely aligned with each other. However, Nitecore paid attention to this detail: when the tailcap is tightened, it aligns perfectly with the flashlight head.
An O-ring seals the tailcap against water. The threads run smoothly and arrived well lubricated.
A tactical flashlight must also operate reliably under extreme conditions. The P27iX is rated IP68 and is protected against water up to a depth of two meters. It is also designed to withstand drops from a height of up to two meters.
The build quality makes an excellent impression on me. The edges and corners are carefully deburred, with only the hard-to-reach inside of the lanyard holes having sharp edges.
Power supply
A special Li-ion battery labeled “NL2155HPi” is required for this flashlight. It differs from standard 21700 batteries in that it has both a positive and a negative terminal on both ends.
This design is necessary because not only the head and tailcap need to be powered, but the rear switches also require communication between both ends. A double-walled battery tube, as sometimes seen in other flashlights, may not have been sufficient in this case. Contact with the battery is established on both sides via spring contacts.
For some reason, CR123A batteries still appear to be widely used in certain professions. With the included adapter, the flashlight can also be operated with two CR123A batteries in series, although with reduced performance. It is important that the two batteries are identical and have the same state of charge.
Unfortunately, 18650 batteries do not fit into the adapter, as its inner diameter is only 17 mm. However, it might be possible to build something similar yourself.
The battery can be charged directly in the flashlight via an integrated USB-C port. While charging also works with a simple 5 V power supply, full charging speed can be achieved with a PD power adapter: in my test, the charging process at 9 V and up to 18 W was completed in just 1:50 h. The charging progress is indicated by four LEDs next to the side switch.
A flip cover made out of metal protects the charging port from dirt and debris. The USB port itself is likely already internally sealed against water ingress. I prefer this solution by far over the commonly used silicone covers, as the hinged lid is much more convenient to open and close. The hinge mechanism is spring-loaded and locks into both the closed and open positions.
During charging, the flashlight can be used normally, with the exception of the brightest modes “Search” and “Lumin Shield”. The flashlight does not include a power bank function.
Attachment
On the tailcap there are two small holes for attaching a lanyard. Unfortunately, the inner edges are quite sharp, so the cord could wear through there over time. In such cases, I usually use a small key ring, but due to the switch there is not enough space for that.
The included “lanyard” comes with an integrated USB charging cable. The USB-C connectors at both ends are inserted into a plastic cap that remains attached to the flashlight. However, as a hand strap, this accessory is completely unsuitable, as its circumference is only 15 cm and is therefore far too small even for children’s hands. A circumference of 30 to 35 cm would be appropriate for a hand strap.
A two-way clip can be attached to the rear end of the flashlight. This allows the flashlight to be attached in a variety of ways, for example to a belt, a pocket or to the straps of a backpack.
If the flashlight is intended to have a fixed place on the belt while still remaining easily accessible at all times, the included belt holster is a good option. The rigid plastic shell is specifically designed for the P27iX and allows the flashlight to be inserted and removed quickly and conveniently. On the back there is a metal clip with an adjustable stopper, allowing the holster to be adapted to different belt widths.
The open bottom of the holster prevents it from being damaged by heat if the flashlight is accidentally turned on. Since the holster cannot be rotated, it is not particularly suitable for hands-free use of the flashlight.
Operation
On the side of the head there is a button labeled “SET” with short travel distance and a precise pressure point. It is used to operate the flashlight in a similar way to the EX7. It is also used to change the settings of the flashlight.
The real highlight, however, are the controls at the tailcap of the flashlight. It consists of two buttons (“MODE” and “ENGAGE”), each with two actuation stages, as well as a sliding switch for the button lock (“Rapid Lock”).
In Basic Mode, operating the flashlight via the SET button shows the same weaknesses as with the EX7: its function depends on how long the flashlight has already been switched on, or how much time has passed since the last button press.
Functions of the SET-button in Basic Mode:
| State | Action | Function |
|---|---|---|
| Off | 1 click | Turn on (Low) |
| Off | Hold | Warning Flash |
| On | 1 click (< 3 s on) | Change brightness (Low → Mid → High → Turbo → Aus) |
| On | 1 click (> 3 s on) | Turn off |
| On | Hold | Change beam shape (Spot → Mix → Flood) |
If you want to turn the flashlight off immediately after switching it on, you either have to wait three seconds or cycle through all brightness levels first. If you want to change the brightness at a later point, the flashlight must first be switched off. Using the rear controls, however, the flashlight can be switched off quickly and reliably at any time: either by briefly pressing the MODE button or by engaging the Rapid Lock switch.
An alternative is the Professional Mode: here, the time-dependent behavior of the SET button is eliminated, so each button press triggers a predictable function. In addition, the flashlight now remembers the last used brightness level (mode memory). The downside is that there is no longer direct access to the lowest brightness level (Low). Turning the flashlight off by holding the button still feels unnatural to me.
Functions of the SET-button in Professional Mode:
| State | Action | Function |
|---|---|---|
| Off | 1 click | Turn on (previously used brightness) |
| Off | Hold | Warning Flash |
| On | 1 click | Change brightness (Low → Mid → High → Turbo) |
| On | Hold | Turn off |
| On | Click + hold | Change beam shape (Spot → Mix → Flood) |
Switching between the two operating modes is done by pressing the SET button three times while holding down the MODE button. To confirm the change, the flashlight flashes once for Basic Mode and twice for Professional Mode.
For everyday use, operating the flashlight via the SET button is only of secondary importance. Much more often, the two buttons on the tailcap will be used, as they provide direct access to four brightness levels and can be customized to personal preferences.
The two stages of the MODE button allow for constant-on or momentary operation and can each be assigned to one of two brightness levels. For the first stage, Low or Mid can be selected, and for the second stage, High or Turbo. To configure this, the MODE button is first held in the corresponding position. A long press of the SET button then switches between the two brightness levels. The width of the beam is adjusted by holding the SET button while the flashlight is on and is saved separately for each of the two switch stages.
Functions of the MODE-button:
| State | Action | Function |
|---|---|---|
| Off | Half press | Turn on (Low/Mid) |
| Off | Full press | Turn on (High/Turbo) |
| Off | Half hold | Momentary Low/Mid |
| Off | Full hold | Momentary High/Turbo |
| On | Half press | Switch between both groups |
| On | Full press | Turn off |
The ENGAGE button also has two stages, each of which can be assigned the modes Search, Lumin Shield or Strobe. Search corresponds to the maximum brightness of the spot beam, while Lumin Shield represents the highest brightness of the flood beam. Both modes offer significantly higher brightness than the regular Turbo levels and are available exclusively in momentary operation. Configuration is done in the same way as with the MODE button.
A “Warning Flash” mode is available to attract attention, in which the flashlight flashes at 5 Hz. In this mode, the last used beam width is applied. The strobe – accessible via the ENGAGE button – operates with a variable frequency of about 16 to 20 Hz, which is intended to enhance its disorienting effect.
Even though the configuration options are fairly limited, there is a reset function for emergencies that restores all settings to factory defaults. To do this, the flashlight is first locked using the Rapid Lock switch. Then the SET button must be pressed three times while holding down the ENGAGE button. A triple flash confirms the action.
Next to the SET button are two sets of status indicators, each with four LEDs that light up for three seconds after every button press. The blue LEDs on the left indicate the currently selected brightness level, while the green LEDs on the right provide information about the approximate battery level.
| Indicator | Battery level |
|---|---|
| ☼☼☼☼ | 75% – 100% |
| ☼☼☼ | 50% – 75% |
| ☼☼ | 25% – 50% |
| ☼ | 10% – 25% |
| ☼ blinking | < 10% |
The indicators can be disabled by pressing the SET button three times while the MODE button is half-pressed, and it can be reactivated in the same way. The status LEDs are controlled using multiplexing, which means that slight flickering can be observed, especially when the flashlight is moved.
From the description, the operation may sound somewhat confusing at first. However, in practical use it quickly becomes apparent that the flashlight can be operated completely intuitively. The configuration is done once according to personal preferences. After that, you will mostly use the two tail buttons.
Currently my flashlight is configured as follows: In Basic Mode, the SET button gives me direct access to the lowest brightness level. This is mainly used for calm situations where no “tactical” access is required. The first stage of the MODE button activates Mid in flood mode, and the second stage activates Turbo in mixed mode. This provides two balanced brightness levels that are suitable for many situations and continuous use. The ENGAGE button is assigned to the two brightest levels, Search and Lumin Shield. The strobe is not of interest to me, so it is not accessible.
In a “tactical grip”, the tail buttons are very easy to reach and can be reliably located at any time, even in stressful situations. The two stages of the buttons are easy to distinguish from one another, although I find the ENGAGE button to be a bit too sensitive. According to the product description, all buttons are made of stainless steel.
| Button | Actuation force |
|---|---|
| SET | 800 cN |
| MODE stage 1 | 1000 cN |
| MODE stage 2 | 1900 cN |
| ENGAGE stage 1 | 200 cN |
| ENGAGE stage 2 | 450 cN |
| Rapid Lock | 750 cN |
What I particularly like is the button lock called “Rapid Lock”. In the upper position, the sliding switch turns the flashlight off and locks all buttons, reliably preventing accidental activation. At the same time, the lock status is always clearly visible and easy to change.
The switch works with a magnetic sensor, so its function can be disrupted by a strong magnet. This can cause the flashlight either to turn off or to temporarily disable the button lock. However, I do not see this as a disadvantage in normal use.
The SET button requires a different grip, which may require repositioning the hand. However, when speed is essential, the tailcap buttons are entirely sufficient.
Illumination
The LEDs are a proprietary development by Nitecore called “M515S”, meaning they aren’t available from any other manufacturer. What makes them special is that they consist of five closely spaced light emitting surfaces, which can be controlled separately in two groups. This allows the effective LES – and therefore the beam pattern – to be adjusted as needed.
The P27iX uses four of these M515S LEDs within a lightly textured quad reflector, protected by a glass lens with a “magenta” anti-reflective coating. In the past, setups with two channels using differently sized LEDs have proven effective. I would have expected an LED with an adjustable light-emitting surface more in a single-reflector design. Examples of this are the Nitecore EDC33 and EDC35, which successfully use the UHi 20 MAX and UHi 40 MAX.
The light has a color temperature of around 5500 K with a neutral tint. A slight color difference is noticeable between the spot and the spill, but it is not distracting. In Search and Lumin Shield, the light appears slightly cooler.
Due to the shape of the reflector and the protruding crenelations of the bezel, clearly visible shadows appear in the spill. However, these are only noticeable on uniform surfaces. In real-world use, they are hardly noticeable.
In practice, the difference between spot and flood is smaller than initially expected. You can see a noticeable change in throw, but both the spot and spill are visible in all settings. A more pronounced effect – ideally with a stepless adjustment – would have been nice.
The most impressive modes are “Search” and “Lumin Shield”. Search corresponds to the maximum output in Spot mode and, according to the manufacturer, can reach distances of up to 430 meters. In Lumin Shield mode, the flashlight operates at its maximum total output, producing a bright and wide light with up to 5,000 lumens.
Spot | Mix | Flood | Search | Lumin Shield
Spot | Mix | Flood | Search | Lumin Shield
Spot | Mix | Flood | Search | Lumin Shield | Reference
Driver and runtime
Nitecore describes the driver as a “highly efficient constant current circuit”, without going into further detail. Based on my observations, I assume it is a buck driver. The brightness and runtime values specified by the manufacturer refer to the maximum output at startup and explicitly do not take thermal regulation into account, so actual performance may vary in practice.
| Mode | Brightness¹ | Runtime¹ | Intensity¹ (Throw²)³ |
|---|---|---|---|
| Lumin Shield | 5000 lm | 22500 cd | |
| Search | 2500 lm | 46320 cd | |
| Turbo | 1500 lm | 2:30 h | 22800 cd 15750 cd 8100 cd |
| High | 400 lm | 6 h | 6642 cd 3249 cd 1806 cd |
| Mid | 80 lm | 25 h | 1024 cd 600 cd 272 cd |
| Low | 15 lm | 100 h | 240 cd 100 cd 49 cd |
¹ According to manufacturer ² ANSI FL1 ³ Spot/Mix/Flood
I limited my measurements to the mixed mode for time reasons. According to the specifications and my experience with the EX7, there are only minor differences between the various beam shapes.
With adequate cooling, Turbo is almost capable of continuous operation. The other levels maintain constant brightness. As the battery charge decreases, brightness is reduced in steps toward the end of runtime until the flashlight eventually shuts off completely. After that, it can still be operated for a certain period of time in the lowest brightness level.
In Search and Lumin Shield, the runtime per activation is limited to 25 and 20 seconds. After several activations, the thermal protection also intervenes and reduces the output before the timer has elapsed.
Thanks to the thermal regulation, the brightness is only reduced as much as necessary to provide the highest possible output. In the process, the flashlight reaches a temperature of about 55 °C.
As expected, initially the heat is focused in the head of the flashlight, but spreads to the rest of the body over time. Since the head can reach temperatures of up to 70 °C with repeated activation of Lumin Shield, some caution is advised to avoid burns.
Thermal images with Zoyi ZT-R02
All brightness levels are controlled without PWM. However, depending on the mode, a varying degree of ripple can be measured with an oscilloscope. The frequency is around 25 to 66 kHz and is therefore not visible to the human eye.
Due to the construction of the flashlight and the special battery used, I was unfortunately unable to measure the current. However, considering the maximum brightness, it can be assumed that it is slightly lower than the EX7 and is likely around 15 to 17 A at maximum level. For the same reason, the cutoff voltage for protection against deep discharge could not be determined precisely either.
Conclusion
The Nitecore P27iX is a tactical flashlight that impresses with a well-designed user interface and four special “M515S” LEDs. The multi-stage tail buttons provide direct access to four brightness levels, while a sliding switch reliably protects the flashlight against accidental activation. Only the SET button on the head requires some getting used to. Also worth mentioning are the battery level indicators and the USB charging port with its metal flip cover.
The width of the beam can be adjusted in three steps – a useful, though not strictly essential feature. In addition to the four regular brightness levels, there are two particularly bright modes called “Search” and “Lumin Shield”. Some of the button assignments can be customized to suit personal preferences.
A major drawback, in my view, is the proprietary battery. A design that works with standard 21700 cells would have been clearly the better option. The NL2155HPi is not only relatively expensive at over $30, but its long-term availability is also not guaranteed.
