Yesterday, I took delivery of a new Fenix PD36 TAC flashlight, with the included ARB-L21-5000U Li-Ion 21700 battery, and a Fenix ALB-10 bicycle mount. I believe I may have mentioned a few weeks ago that I was thinking of getting one, and I finally did.

I took advantage of last week's 20% off Labor Day sale. This is my third Fenix flashlight (or fourth, if it's really true that my Leatherman Serac S3 was really made by Fenix), and my first with a Li-Ion cell (21700, specifically the included Fenix ARB-L21-5000U with integral USB-C charger). I also own an E12 v2.0 and an HM23 headlamp that I purchased earlier this year.

The first thing that struck me was how small the box was. I was honestly expecting the PD36 TAC to be bigger, but it's much smaller in person than I expected. It almost makes me wish I'd held out for the upcoming TK28 TAC, which will be effectively the same flashlight with a larger reflector head and the same operating mechanism. But, the truth is that one of the reasons I decided not to wait any longer was that I plan for the PD36 TAC to serve two purposes in my life. The first is as my bicycle headlamp, for which purpose I also ordered the Fenix ALB-10 bicycle handlebar mount, and the second is as a personal carry tactical flashlight, so I decided it was probably a better idea for me to get the more compact version for when I need to carry it in my handbag.

The E12 v2.0 serves as my EDC flashlight that is part of my standard EDC survival gear that is always in a little Martha Stewart zipper pouch in my handbag. The HM23 is my headlamp for camping/hiking/backpacking. I chose the PD36 TAC because of its advertised runtimes of 160 hours @ 30 lumens, over 18 hours @ 150 lumens, and over 10 hours @ 350 lumens, all with totally flat brightness curves. I do not expect to ever have much need for the 1000 lumen, 2000 lumen and 3000 lumen modes, but it's nice to know they are they should I ever need them.

I also chose it because of the fact that it has mechanically selectable lock-out, "duty" (utility), and "tactical" modes. Being a non-professional user, it's the duty mode that I will be using, which gives access to the Eco (30 lumen), Low (150 lumen), and Med (350 lumen) modes, as well as the High (1000 lumen) , Turbo (3000 lumen), and Strobe (2000 lumen) modes, in that order. The tactical mode gives access to a 2000 lumen mode (click on) and Strobe (press and hold) modes only, so that in high stress situations, there's very little chance of operator error.

In my recent rides to the market at night while grasping my E12 v2.0 in one hand, I've decided that the 160 lumen mode is just fine for medium speed riding at night, while the 30 lumen mode really isn't enough even for slow speed riding, so I think that for my bicycle, the 150 lumen mode should work great, and I can still use the 350 lumen mode without fear of killing my battery. I am also a motorcyclist, and I learned from that practice that having a daytime running light is excellent for safety. I plan to use the PD36 TAC for that purpose, as well, and the long battery life means that I will never really need to worry about it. I live at the South end of my town, and my office is at the North end of town, a distance of about 3.5 miles, with a major shopping centerless than a mile further away. So, most of my needs can be met within 5 miles of my house.

My future plans include getting myself an e-bike, so the 350 lumen mode will be good for its 20-25 mph max speeds, I think.

This is the first light I've ever owned with 350+ lumens output. I do also own a Bushnell 20154 (2xCR123A) flashlight that supposedly puts out 325 lumens, but I never use it anymore, because of the fact that CR123A batteries are stupidly expensive where I live (for the same reason, I no longer use my Serac S3), and because the sharply machined, knurled, and crenellated body is extremely uncomfortable to hold and would destroy any fabric to which it was clipped. The PD36 TAC has no annoying sharp edges.

The first criticism I have is that the PD36 TAC does not contain any instructions as to how to charge the battery, and there is no separate instruction sheet for the battery included. Considering that Fenix sells the battery separately, I would have expected in instruction sheet for the battery would be simple to drop in the box. A brief look at the Fenix website indicated that the recommended charging current is 1A, and the maximum is 5A, so in the interests of safety and hopefully best battery life, I elected to plug the included USB-C to USB-A charging cable into one of my old Apple iPod/iPhone 5 V/1 A USB-A chargers. I also have an Apple iPad 20 W (4 A) USB-C charger, but I was a little wary of using that. The battery has a tiny LED charging indicator in the center of the anode the glows red while charging and blue when charged. Quoted charging time is "about 4 hours", so it should be good to go later this evening, if I decide to ride my bicycle to the market, which I probably will, because I forgot to buy rice the other night, and I'm Asian, so rice is a necessity. smile I have less than one serving left in my rice tin.

While the battery is charging, I got out the ALB-10 mount and inserted the body of the flashlight. It turns out that the top half of the clamp must be removed entirely from the mount in order to insert the flashlight, which is a minor annoyance. The ALB-10 mount seems like it will work well, but I was hoping before I found out otherwise that the flashlight clamp had a quick release; rather, the quick release detaches the flashlight clamp from the handlebar clamp, rather than releasing the flashlight.

This means there will be no quickly grabbing the light off the bike and being able to use it without the clamp attached to it, which is awkward, at best, if you are facing a sudden need for self-defensive use. Fortunately, I live in an area with a very low rate of violent crime, but unfortunately, we have a relatively high rate of property crime. At least I will be able to quickly detach the flashlight clamp from the handlebar clamp and drop it in my handbag when I get to the market, so I don't have to worry about it being stolen. Other than that, the mount seems strong and stable. The clip on the flashlight does not impede mounting the flashlight clamp.

If I know I'm not going to be riding my bicycle, then it only takes a few seconds to remove the flashlight clamp from the body or put it back in, and the compact size of the PD36 TAC means it's not going to be a problem fitting it into my already over-stuffed handbag. I would just caution against over-tightening the flashlight clamp, since the clamp is made of nylon. It has rubber inserts, so it doesn't take a lot of torque on the thumbscrews for it to hold the light securely, and leaving a little give in the rubber will help it dampen vibrations better.

I haven't even attempted to turn it on, because I don't want to do that before the battery is fully charged. Superstitious, I know, but it's only a minor inconvenience to my need for immediate gratification with my new toy...I mean, tool.

In the future, I plan to buy at least one more Fenix ARB-L21-5000U battery, and a Fenix USB-C charging cradle (not yet shipping) for it that can also be used to turn the battery into a backup cell phone charger. I didn't want to shell out the money for a second battery this week, but having only the one battery shouldn't be much of a problem initially.

I was considering also getting an E20 v2.0 (2xAA) for household use, but since the PD36 TAC's Eco mode is the same 30 lumens as the E20 v2.0's Low mode, I may forgo that idea. I like the idea of having a household flashlight with primary cells for power outages and such, since that would avoid self-discharge, but because my usage patterns with the PD36 TAC will keep it in frequent use, and because it has such a huge battery, I'm less worried that I used to be about the idea of self-discharge and battery maintenance. And because the PD36 TAC will be either on my bicycle or in my handbag, I will also know where it is immediately if the power goes out.


The battery is now fully charged and installed, and the first thing that I discovered is that the tailswitch requires a *substantial* amount of force to fully depress, so much so that for about five minutes, I thought it was defective. I think the spring could be lighter, but I think I can live with it. Since I play bass guitar, my fingers are strong enough to operate the switch reliably; I just wasn't expecting it to require that much force. The button goes it, hits a stop (the "tap" switch), and from there you must apply a much greater amount of force to fully depress the activation switch. I can imagine people who don't have hands as strong as mine having some difficulty with this.

Second, I did not get from my initial read of the product documentation that in Duty Mode, the light will save the previous brightness mode, rather than starting from Eco Mode. Given that this is a true tactical flashlight and not really a utility flashlight, I can live with this, because at least it does not always turn on in its highest brightness mode first, forcing me to always cycle through to find a lower brightness mode, meanwhile killing my night vision and battery life.

Otherwise, I have no complaints about the operation of the PD36 TAC.

First ride report:

Attaching the handlebar mount to the bicycle was easy, requiring a single thumbscrew. The mount holds securely with none of the rattling reported by one YouTube review. Separation of the two halves of the bracket at the destination is simple, and after riding slowly for a mile to the market at the 150 lumen setting, there was no noticeable heat from the flashlight when I put it in my bike bag (which is actually a Timbuk2 Metro bag with two cheapo carabiners that I can slip over the handlebars easily. My bicycle is a 1990s era Trek 820 mountain bike that I bought at a local charity shop for $25. I put a rear rack on it and used heavy duty zip ties to attach an old milk crate for my handbag, office briefcase, and groceries.

I did test all the brightness settings. As I expected, the 150 lumen setting is perfect for casual pedalling, while the 350 lumen setting is perfect for the 20-25 mph downhill coast through a stretch of no streetlights on my way home. If and when I am actually able to upgrade to an e-bike, I think this light will work perfectly. The 1000 lumen and 3000 lumen settings are pretty stunning, although I didn't keep them on for long enough to even see the output drop, 5-10 sec at most before cycling to a lower brightness mode.

Even though the 350 lumen setting is quite bright enough for riding at the speeds I will experience at night, having that 1000 or 3000 lumen "high beam" mode for my bicycle headlamp is a comfort. Although I am a townie, I never forget that the town is still in Northern New England, and I am on the edge of it, which means that black bears and moose are not entirely out of the question, although I am more afraid of the large population of skunks in this area. laugh

Beam collimation is actually quite good for use as a bicycle headlamp, I think. Not too narrow, not too wide. Presuming the TK28 TAC will actually have a tighter beam due to the bigger reflector, I think the PD36 TAC is probably the better choice for a bicycle light.

This not being a dedicated bicycle light, not being able to change brightness settings in both directions is a downside, but it's acceptable, since even while riding, it's easy enough to unlock the switch, cycle through, and lock it again (if you keep it locked while riding). Fenix' dedicated bicycle lights actually suffer from the same defect, so it's not as if I'm missing much, anyway. Besides which, Fenix' newest bicycle light, the BC30 v2.0, uses two 18650s, and I'd much prefer the single 21700 battery of the PD36 TAC.

On my return trip, I experienced some flickering at the 30 lumen setting. This was slightly troubling, and I will keep an eye on it. The flickering may have been due to the flashlight being cold (outside temp 60 deg F). There was no flicker on any other setting, and after running the light on a higher mode for 10 sec or so, the 30 lumen mode was then flicker-free, presumably the emitter or controller having come up to stable operating temperature. And now that I am home, it is rock solid stable at room temp. But, that is a bit worrying, if I end up taking this light out in Winter. We'll see.
Gemma Seymour (she/her) @gcvrsa