Fenix PD36R Flashlight Review

The Fenix PD36R flashlight is a very feature-rich 21700 light.  It has USB-C charging, dual switches, and other cool features.  Read on!

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Official Specs and Features

Here’s a link to the Fenix PD36R flashlight 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.

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Short Review

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

Long Review

The Big Table

Fenix PD36R Flashlight
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:  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

• 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.

Here’s the test light with the venerable Convoy S2+.  Mine’s a custom “baked” edition Nichia 219b triple.  A very nice 18650 light.

And here’s the light beside my custom engraved TorchLAB BOSS 35, an 18350 light.  I reviewed the aluminum version of that light in both 35 and 70 formats.

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.

Charging

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

Pulse Width Modulation

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.  Also, here’s the light with the worst PWM I could find.  I’m adding multiple timescales, so it’ll be easier to compare to the test light.  Unfortunately, the PWM on this light is so bad that it doesn’t even work with my normal scale, which is 50 microseconds (50us). 10ms.  5ms.  2ms.  1ms.  0.5ms.  0.2ms.  In a display faster than 0.2ms or so, the on/off cycle is more than one screen, so it’d just (very incorrectly) look like a flat line.  I wrote more about this Ultrafire WF-602C flashlight and explained a little about PWM too.

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 (KillzoneFlashlights.com 219b version) (affiliate link)

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

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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!
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