Fenix PD36R Flashlight Review

Today I have in for review a very feature-rich light by Fenix.  First off, it’s a 21700 light, which is great.  It also has on-board charging (via USB-C), dual switches, and some other cool features.  Read on to see how it tests out!


Official Specs and Features

Here’s a link to the official product page.

Versions

There’s only one version of this light.  Custom Shop finishes by Fenix are available for this model, however.

Price

The light is sale priced at $99.95.


Short Review

I can’t think of a thing to complain about on this light.  It meets its specifications, and is a reasonably priced complete package light.

Long Review

The Big Table

Fenix PD36R
Emitter: Luminus SST40
Price in USD at publication time: $99.95
Cell: 1×21700
Turbo Runtime High Runtime
LVP? Yes
Switch Type: Dual
On-Board Charging? Yes
Chargetime
Power off Charge Port with no Cell? No
Claimed Lumens (lm) 1600
Measured Lumens (at 30s) 1817 (113.6% of claim)*
Claimed Throw (m) 283
Candela (Calculated) in cd (at 30s) 719lux @ 5.451m = 21364cd
Throw (Calculated) (m) 292.3 (103.3% of claim)*
All my Fenix reviews!

* Measurement disclaimer:  I am an amateur flashlight reviewer.  I don’t have $10,000 or even $1,000 worth of testing equipment.  I test output and such in PVC tubes!!  Please consider claims within 10% of what I measure to be perfectly reasonable (accurate, even).

What’s Included

  • Fenix PD36R Flashlight
  • Fenix 5000mAh 21700
  • Charge cable (USB to USB-C)
  • Nylon pouch
  • Lanyard
  • Spare o-ring
  • Spare switch boot
  • Manual and paperwork

Package and Manual

Typical Fenix black and orange(ish) package.

The manual is good, and displays many (7 or 8) languages.

Build Quality and Disassembly

The PD36R is well built.  There’s nothing glaringly bad, and everything works like it should.  I like the e-switch cover in particular, as I’m partial to metal switch covers.

The sticker inside the tube is a shade confusing.  That’s not a “negative” symbol – don’t put the cell with the negative end here.

The tail end of the light has a big thick spring.  This is a two piece body, and best I can tell, it’s not possible to access the mechanical switch.

The head end has only the contact points – no spring.

The threads are appropriately lubed, anodized, and square cut.  They’re very smooth threads.  Because of the anodizing, it’s possible to mechanically lock the light out (though it’d be meaningless, since the tailswitch is mechanical).

The driver looks to be screwed in, and there are two holes for unscrewing.

Size and Comps

Officially:

Size:
Length: 5.4” (136mm)
Body: 1.0” (25.4mm)
Head: 1.0” (26.4mm)

Weight: 3.0 oz. (85g) excluding battery

Here are a couple other 21700 lights.  They have different feature sets; it’s understandable why the PD36R is longer.

Retention and Carry

There’s a nylon pouch included.  There’s no good reason the light won’t go in the pouch in either orientation, except the pocket clip….  every time I tried bezel up, the clip caught as seen in the left picture.  If you decide to futz with that, then it’ll physically fit.

Also for retaining the light is a two-way friction fit pocket clip, which attaches only on the tail end.  It’s quite snug, and can hold the lanyard thorough a hole in the shoulder.

An included lanyard rounds out the package.  It may be attached on the pocket clip, or even better, through holes in the tailcap.  The photo below gives a good picture of why the light won’t tailstand – the boot is very proud.

Power and Runtime

Fenix includes the cell appropriate for this light.  It’s a 21700 cell, in this case a button top.  Fenix labels this as a 5000mAh 21700.

Runtimes for Turbo and High follow.  The drop off Turbo is fairly quick, then the light holds 1400 lumens for a good 20 minutes, then around 950 lumens for around 100 minutes.  The light didn’t shut off, but output became so low, you’ll notice lowered output.

High output is stable for around 20 minutes, then rock solid flat for 320 minutes.

The PD36R includes on-board charging, and impressively it’s via USB-C.  A USB to USB-C cable is included.

The charge port cover works fairly well, and stays put when it’s pressed down.

I’m charging here from a USB port capable of around 2.4A, and the USB-C Fenix seems to like it.

I don’t know why the charging bounces around like this, but it still stays at a high current, and charges quickly.

Despite being USB-C, the light can not output power from the port.

Modes and Currents

Mode Mode Claimed Output (lm) Claimed Runtime Measured Lumens Tailcap Amps
Turbo 1600 2h50m 1817 4.36
High 800 5h49m 909 1.43
Medium 350 8h24m 374 0.50
Low 150 26h 155 0.2
Eco 30 115h 31 0.04

PWM

This isn’t actually PWM, it’s … that other thing I can never think what it’s called.

For reference, here’s a baseline shot, with all the room lights off and almost nothing hitting the sensor.  And here’s the worst PWM light I have ever owned.  Also one of the very first lights I ordered directly from China!

User Interface and Operation

There are two switches on the PD36R. The first is a mechanical tail clicky. If this switch is “on”, then the light is on. If this switch is “off” then the light can not turn on.


The second switch is a side, indicating e-switch, made of what looks to be copper, but is likely bronze coated metal.  The center of the switch has an indicator behind it.

This is a good dual-switch interface.

Here’s a UI table!

State Action Result
Off Click Tail Switch (TS) On (Mode Memory)
Off Half press TS Momentary memorized mode*
On Click TS Off
On Hold SS Strobe
Strobe Click SS Previous mode
On Click SS Mode advance (L>H direction)

* Modes may be changed with SS while half pressing TS.

LED and Beam

The emitter Fenix chose for this light is a Luminus SST-40.  The reflector is smooth and deep.

When the head is tightened down, the indicating switch tells how much power the cell has.

Green Steady: 85-100% power
Green Flashing: 50-85% power
Red Steady: 25-50% power
Red Flashing: 1-25% power

The switch also indicates when the cell power is low during use; red flashing only.

Light is able to escape when the light is headstanding.

These beamshots are always with the following settings:  f8, ISO100, 0.3s shutter, and manual 5000K exposure.

Tint vs BLF-348 (Killzone 219b version)

I compare everything to the Killzone 219b BLF-348, because it’s inexpensive and has the best tint!

Conclusion

What I like

  • Meets and exceeds specification
  • Good complete package light
  • Utilizes USB-C for charging
  • Fast charges the 5000mAh 21700
  • Metal e-switch cover
  • Indicating side-switch

What I don’t like

  • No direct access to low
  • Overall long light
  • Can’t tailstand

Notes

  • This light was provided by Fenix for review. I was not paid to write this review.
  • This content originally appeared at zeroair.org.  Please visit there for the best experience!
  • Whether or not I have a coupon for this light, I do have a bunch of coupons!!  Have a look at my spreadsheet for BangGood and GearBest coupons. Please subscribe and get notifications when the sheet is edited!!

Author: zeroair

11 thoughts on “Fenix PD36R Flashlight Review

  1. Hey, could you help me. I need to see if the PD36R can be charged using usb-c to usb-c. Like from a cell phone charger that has a usb-c to usb-c cable. Not original usb (type A) to usb-c. Could you test for me please?

    1. Tested it this morning, and yes, the PD36R seems to work fine on a USB-C to USB-C cable. Looks to charge at around 1.15A or so (quick test only).

  2. PD36R instance with a cold, freshly turned on light, flicker (PWM) is very noticeable in the first 30 lumen mode. however, it is worthwhile to “warm up” the lamp for at least 10-15 seconds in the 800 or 1600 lumen mode, and after that even in the 30 lumen mode the flicker (PWM) completely disappears.
    in all other modes above 30 lumen even if you turn on the lamp from a cold state. no flicker (PWM).
     in your photos with PWM measurements, my version is clearly indirectly confirmed. PWM is clearly in 30 lumen mode.
    Does the same thing happen with your PD36R instance?

    1. I don’t really know the answer to your question. I did test from low to high, so maybe the readings would be different if I warmed the light up in higher modes? But I don’t find that to be a realistic use scenario for me. If I want low I’m going to start in low. And if low has PWM, well then….

      Also this isn’t true pwm. It’s more commonly referred to as “sawtooth” but I still can’t remember the proper name for this.

  3. zeroair,
    And still!
    please try to turn on your PD36R in ECO mode (30 lumens) when it lies at room temperature for several hours and completely cools down.
    Do you notice how the hotspot blinks (as if flickering at a low frequency)?

    1. Maybe I’m not exactly sure what you’re asking but….

      I just turned the light, which was at room temperature, on into Eco mode, and watched the output via the scope (ie, for PWM) and after any amount of time it looks exactly like the PWM test in the ECO mode shown in the PWM section. It doesn’t change to any lower frequency, and it doesn’t seem to be flickering visibly.

  4. Is the step-down in Turbo and High due to thermal regulation? If I use this in a cold climate will it still decrease to ~450 lm in High? I want to use this as a helmet light for snowmobiling but I don’t thing 450 lumens is bright enough. Any idea what the throw would be at that level?

    1. The step down at 20 min. mark is timed on both Turbo and High, regardless if the light is cold or not, it will step down after 20 min. Of course you can bump that up again, no problem.

  5. Thanks for this straight forward review.
    I really like Fenix lights but I want them to have direct access to low lumens. If they let you push and hold the side switch to access a super low lumen made that would be awesome.
    Could you recommend a light similar to this one with internal charging capabilities, tail switch and instant access to a low light mode?
    Would the thrunite TC15 be comparable?
    Thanks.

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