A New Benchmark Flashlight: Fenix PD36R Ace Review

Powerful, nuanced, long-running, and durable, the PD36R series of flashlights has been my top choice for at least 2 years. Now, with a slight boost in power and a major change in the user interface, the PD36R Ace might be the best flashlight on the market today.

It comes down to your choice in controls — tail switch versus side switch. But for those who like a side switch, the new Fenix PD36R Ace is a brand new benchmark in small, versatile flashlights for everything from camping and hiking to hunting and tactical use.

I’ve tested this light for about a month. It’s top shelf. Here’s why.

In short: The Fenix PD36R ACE ($110) produces up to 3,000 lumens in a pocketable-size flashlight. With a throw out to 1,362 feet (415 m) and a max run time of 63 hours, 25 minutes on 30 lumen eco mode, it knocks performance way out of the park. But where it steps away from the field is through its Advanced Command Edition (ACE) SET button. It allows users to customize output modes for specific tasks and preferences, something rarely found in mainstream brands. That, coupled with a wonderful user experience, makes this one of the best flashlights you can buy today.

Compare the Fenix PD36R ACE with the other best flashlights on GearJunkie’s guide to the Best Flashlights.

Fenix PD36R ACE, A New Option in the Family

Before I get nerdy with flashlight testing, I’d like to point out that this is a ridiculously good flashlight. If you’re looking to buy a top-tier, modest-size flashlight for hiking, hunting, work, camping, or just general life, you’ll be hard-pressed to find a better, more versatile flashlight in the $100 price range.

There are a lot of good ones out there, yes. Better? That’s arguable. So if you like this one, just get it. You won’t regret it.

Now, onto the nerdy part.

I’ve been testing the Fenix PD36R family of lights since the summer of 2023, when the PD36R finally beat out (in my opinion, at least) the PD35R series. These are very similar flashlights, so we’re splitting hairs. But when you have to crown a best flashlight, that’s what you do.

And now, splitting the hairs further between the PD36R family (Pro, ACE, and V2), I think the ACE comes out on top. But this is mostly a matter of personal opinion and what type of interface you prefer. I’ll break that down later, but first, let’s talk specifically about the ACE.

PD36R ACE Review

The Fenix PD36R ACE oozes quality in the hand. The anodized black A6061-T6 aluminum body is meticulously machined. The sample I received for testing was flawless. The tail cap screws off with firm but smooth resistance, revealing a 5,000mAh 21700 battery. Its removable nature is great, as it allows both battery changes and replacement, extending the flashlight’s lifespan nearly indefinitely.

Moving to the front of the light, a strong pocket clip attaches near the rear before a textured grip. Then, a hidden ring again unscrews smoothly to reveal a USB-C charging port and the SET button, which allows users to customize the lighting outputs.

Forward of the ring is a side switch, which controls brightness or fires strobe modes.

Finally, the business end has a Luminus SFT70 Gen2 LED housed behind a toughened ultra-clear glass lens with an antireflective coating. A fixed reflector focuses the light to a strong central spotlight with generous spill in a secondary halo.

The light itself is smooth and consistent, as you’d expect from a high-end light. I’ll admit that the junction between the spot and the spill isn’t perfect. There are a few areas of fuzz between the two brightness levels, and the central spot circle isn’t perfectly round, but it’s very close.

And let’s be real, these aren’t binoculars. For a flashlight lens, this thing is darned nice.

User Interface

The PD36R ACE has a tactical tail switch for instant activation and a neck-mounted side switch for output selection. This combination is ideal for many users, especially those who usually hold a flashlight at their side, as when walking.

Press the tail switch to turn the light on and off. Soft-press it for momentary light — it’ll turn off immediately upon release unless you deep-press the switch. From “on,” press the side switch to scroll through lighting modes. The side switch lights up with a battery indicator at turn-on, but that light turns off after a few seconds.

It’s one minor critique: Finding the side switch with gloved hands in the dark can be a little tricky. Once located, it’s easy to use, but I have found myself needing to turn the light off and back on to locate the switch with its glowing battery indicator.

In contrast, the PD36R Pro has dual tail switches. That setup may be better for some tactical or law enforcement uses, as it prioritizes an overhand grip and thumb activation of the controls.

Think of someone looking into the windows of a parked car; they’d hold the flashlight with an overhand grip, light at shoulder level. Beyond the location, it’s instantly accessible every time, no hunting for a small button to adjust levels.

But if you’re hiking, camping, walking a dog, or working around a house, the side carry is more natural. Of course, you can use either light in either grip, but it’s a subtle difference of prioritizing one over the other.

The side (or neck) switch, for me, has proven wonderful for most uses. I don’t work in the military or law enforcement, so I don’t expect to use a light in tactical situations much. That said, there is no reason at all that I couldn’t use the PD36R ACE with an overhand grip. And its strobe is no joke as a defensive tool.

SET Button

A unique tool in the Fenix ecosystem, the PD36R ACE (and other ACE flashlights) has a “SET” button under a protective ring. Using this small button, the user can customize the light to one of three output modes. It is very easy to use and takes just a few seconds to switch the modes. The graphic below from Fenix explains the user options.

As you can see, the options offer dramatically different performance. Option 1 simply turns the light on full blast every time. I could see that being useful in certain situations, although probably not ones I’d use it for much. It strikes me as a tactical use case. But options 2 and 3 are tailored to campers and hikers.

I found myself setting the light in option 2 mostly, as the three settings offer easy battery management. Fire the light on Turbo for brief glimpses at range, and then dial it to medium or low for most use. In that manner, you’ll get an astounding amount of lighting hours out of the flashlight.

Durability

The PD36R ACE is IP68 dustproof/waterproof. That means its submersible up to 2 m.

In testing, I used the light for over 2 weeks of hunting in the Rocky Mountains in September. Several nights were below freezing, and the light was exposed to both rain and snow. I also carried it for several days in a backpack, bouncing around among my other gear.

This testing didn’t put a scratch on it, nor did it mind the wet or cold. Back home, I put it to harder service. First, I froze it in a deep freezer set at 4 degrees F for 1 hour. I left it on low. Then, I turned it off and put it back in the freezer for another half hour. In short, it was fine.

Then, I submerged it in a 5-gallon bucket of water for an hour. As expected, it was unscathed by the submersion. I left it in the bucket overnight, for about 15 hours in total. It was perfect when I took it out. There were no water intrusions into any of the sealed parts.

Build Quality

The Fenix PD36R ACE feels luxe in the hand. The cold aluminum barrels have a precise texture that is perfectly repeated around the flashlight’s body. The pocket clip is strong enough to hold the light in place but still flexible enough to easily latch onto a pocket.

The screw-in tailcap is snug and smooth to open and close. It feels like a perfect fit. It seats on an O-ring for waterproofing, and ships with an extra. The gold-colored spring contact for the negative terminal is stiff and feels very durable.

Overall, this light feels built to last. If it has an Achilles heel, it would be long drops. As with almost all flashlights, any drops over 1 m will be questionable. I’ve dropped several Fenix lights further than that without issue, but it comes down to luck and how it contacts the ground, rock, or concrete as to whether the light will survive.

Performance

The PD36R ACE has top-shelf performance. In turbo, the 3,000-lumen output is incredibly light. That said, it does get hot quickly, no surprise for such a high output in a small light.

In testing, I turned it on turbo and left it there, something I’d rarely do in real-world use, to see how it fared compared with Fenix’s claimed values. Fenix rates its lights per the ANSI PLATO FL1 standard. Being a Portable Lights American Trade Organization (PLATO) member, I trust its claimed ratings pretty well.

As I suspected, the runtime held up pretty true to form. I noticed a slight drop-off in power around 3 minutes in, then another slight decline around the 19-minute mark. It was still really bright, though, pumping out very bright light a full hour later, before I shut it down. I’ll be doing further testing.

It’s worth noting that, by that time, the light was really hot. I could still hold it in my hand, but in real-world use, I would have absolutely turned the light down a notch before it got that hot.

I think it’s worth noting that turbo mode on this light is wildly bright. For anything other than long-distance searching, it’s overkill.

In real use, I ran the light mostly on its medium, 350-lumen setting. For example, I helped a friend blood-trail an elk he shot with a bow for several hours one night (we did eventually recover it). During the search, I ran the light mostly on medium as I moved from blood spot to blood spot.

But from time to time during the search, I bumped the light to turbo to look farther ahead for blood or the animal. But most of those turbo blasts lasted for less than a minute.

Running on medium, the light never got much beyond warm. In turbo, the whole light gets hot. Not too hot to hold, but close.

Where the light performance really shines is on the lower settings. I love using a light around 30 lumens in a tent or around camp. It’s usually enough to see, and it doesn’t kill your night vision that badly. And at 30 lumens, this thing goes for days — literally, 63 hours. At 150 lumens, which is plenty of power for a brisk walk on a trail, it runs for a remarkable 22 hours, with falloff only at the very end.

Fenix PD36R ACE: Who It’s For

The Fenix PD36R ACE is a slightly expensive flashlight, but at $109, it seems like a great value. Yes, there are a lot of pretty good flashlights for $50 or less. But if you want to step up to premium output and performance, the price for the PD36R ACE seems really reasonable.

The excellent battery life, ideal size, incredible output, and customizability make this light ideal for many uses. Hunters, hikers, campers, law enforcement, mechanics, construction workers, industry — the list goes on, but I don’t see many flashlight needs when this wouldn’t be a darned good choice outside of scuba diving (it isn’t rated for that much depth).

But for most people, shoot, this light is a one-and-done that will do most anything you’d want.

It’s a bit on the large side for EDC, though. If you really do carry a flashlight all the time, you may want to consider trading the remarkable performance of the PD36R ACE for a bit smaller form factor.

However, if you’re looking for a light that will fit in a glove box, pack, or even pocket, and light up the night for many hours in a row, the Fenix PD36R ACE is a wonderful choice. After a little more testing, it may become the flashlight that I judge all others against.