(REVIEW) Sofirn TF84 - another review

A well built light with a unique UI that lends itself to tactical applications. An 18650 light with USB-C charging and a remote tail switch option.

A quick look at the Sofirn TF84. I got this from Amazon with the discount code for $30. Thanks Sofirn!

The light arrived packed in a cardboard Sofirn box, rattling around inside a larger Amazon box with no padding inside at all. Still the Sofirn packaging was undamaged.

Inside the Box was: the light, the remote tail switch, 2 spare O-Rings, a Sofirn branded 3000mAh battery, and the instructions.
The instructions and description indicate that there should have been a USB-C charging cable included.
Mine did not have this.
This light can run off an 18650 (Flat tops work just fine). Or two 123s.


The finish on the light is excellent. The tail cap threads are square cut and move smoothly.


This light is different than any other light I’ve owned. I really need to make a video to show it off. But I’ll give it a go here.
First off, there are two buttons on the tail cap. A round mechanical push button (called Main).
And a crescent shaped e-switch (called Mode).

End Cap

The Main button is a forward clicky with momentary on at the half click position.
Pressing the Main button always activates Turbo. A full click and the light stays in turbo.
From off, pressing the tail Mode button always activates Strobe. This is a momentary on button.
Holding the tail Mode button on for more than 2 seconds – will turn on strobe constantly.

From off, turn on the light with the tail Main switch. Now the tail mode switch will cycle through the brightness levels. The available levels will depend on which group is selected. Outdoor or Tactical.

There are two groups available. Outdoor and Tactical. In Outdoor, Low, Medium, High, and Turbo are available using the tail Mode switch. In Tactical group, only Turbo and Medium can be selected. Turbo always come on first. Then a push of the tail Mode switch will step it down to medium.

Confused yet? Just wait!

Tail Switch

There is a remote tail switch that can replace the normal end cap. There are two active areas on the switch. The long strip seen on the left in the image duplicated the function of the tail Mode switch. A momentary press turns on Strobe.
The bump on the right side of the switch duplicated the tail Main switch. It is a mechanical forward clicker.

Side Switch

In addition to the two tail switches there is a side e-switch located on the head. This switch can work in conjunction with the tail switch or independently.
From off, a press and hold will turn on moonlight. Additional presses will step the light to the higher brightness levels. Hold to turn off the light.
From off, a press of the side switch will turn on the light. This has memory, so it will turn onto the last brightness level.

From on or off. A double click of the side switch will activate strobe. A single click will cycle through the Strobe – SOS - Beacon blinkies.
BTW, the strobe varies between about 7Hz and 16Hz, light painters take note.

Now, if you turn on the light with the tail Main switch, the side switch changes the brightness levels.
If the light is turned on with the tail Main, it can not be turned off with the side switch. It must be turned off with the tail Main.

However, no matter if the light is on, off, or set to a lower brightness level, pressing the tail Main switch ALWAYS turns on turbo.

The Side switch has an LED in the center that indicates battery level and charging condition.

Still with me?
It is possible to lock out the side switch so that only the two tail switches will control the light.
They act in the manor described above.

This, I think, is the ideal way to use this light. If you think of this as a tactical light, there is really no reason to have anything other than Turbo, Medium, and Strobe (in the tactical group). Or Low, Med, High, Turbo, and Strobe (in the outdoor group).

For those who have requested a light with instant one button Turbo or Strobe – Well here it is.

Mechanical Lockout

The tail cap threads are not anodized. Unscrewing the tail cap will not lockout the light in all modes (just go with me on this one).
The head threads are anodized and the light can be locked out by give the head a half twist. The head was on quite firmly and needed some muscle to turn the first time.
BTW, the head threads are not square cut.


Length from bezel to tail switch: 5.61”, 142.5mm
Tail Cap Diameter: 1.066”, 27.1mm
Body Tube: 0.988:, 25.09mm
Head: 1.38”, 35.16mm
Lens: 1.07”, 27.2mm
Weight w/Batt: 5.7oz

Note that the tail switch extends beyond the tail cap ridge.
This light will not tail stand.

When mounting the light, the tube is just shy of 1”, You may need to add some padding to make the light a tight fit in the mounting rings.

The Battery
The battery came installed in the light with a disk over the negative end to prevent accidental turn on.
The battery measured 4.06v out of the box. So basically fully charged.
The included Sofirn battery tested to 3007mAh. After the second run time run. 3182mAh of angry pixies marched back into the battery.
As a side note. Every Sofirn battery I’ve tested has always exceeded its rated capacity.

Take a look at the button top. I see the vent holes look to have the same problem as reported in the more recent Sofirn LT1 and SP36 lights. The holes have burrs that extend above the button top and have rough edges. In a light that has a ring top contact, these will scrape brass off the ring and create a dangerous condition inside the light.

Not a problem in this light as the button top doesn’t scrap across anything. Just be aware not to use this in a light that has the other type of connection.
As a side note, my older Sofirn batteries that came in my LT1, and two SP36s, don’t have this issue.

Parts is Parts
Of interest is construction. There is a secondary tube inside the main body tube. It is anodized on the inside and out. The ends are bare. The battery spring in the head fits through the end and connects with the positive end of the cell.
This, I assume, is how the two tail switches communicate with the driver in the head.

The light has a USB-C Port opposite the switch in the head. The USB port cover is quite thick and actuall protrudes more than the e-switch. It does fit quite firmly in the port.
But – inside the Port is open to the guts of the light. Lose the Port cover and the IPX8 rating drops to a don’t’a get me a’wet or I die.

I would argue that a “tactical” light should not have an charging port that can be opened to the elements with the flick of a rubber cover.
I only saw about .9A of current when the light was hooked to a QC3 USB power supply. I had to use a A to C cable I had on hand as the one that was supposed to come with the kit was absent.
The battery measured 4.17v after charging inside the light. Good Job! I had rather the charge stay on the conservative side.


As you can see the light is very well controlled. Those are about as straight a line as you can get.
The battery measured 2.6v after the timed runs. These ran overnight, so that’s the voltage cut off.

If a light has crappy PWM, it is unusable as far as I’m concerner.
The TF84 has none. It is current controlled.
You can see some artifacts from the driver but the voltage is always a positive offset.


Of note, there are actually 2 low levels. One is reached the normal way via the side or tail switch.
The second is reached by using the side switch to go to moonlight. Then step up to low. Strange but true.
Low 2

Low 1

Both the low(s) have notable artifacts from the driver. These do not show in real life.
The strobe has two alternating Freqs. about 7Hz and 16Hz

Here is the only disappointment. All my other Sofirn lights measure close to the rated outputs. This on falls short.
I retested with a Sony and a 30Q. Both put out a few more Lumens at the top end than the Sofirn battery. The below is for the TF84 with the Sony battery.

Mode: Spec, Measured
Moonlight: 1, 0.6
Low(1): NA, 6.5
Low(2): 10, 16
Medium: 150, 156
High: 450, 377
Turbo: 1200, 900 (turn on) 862 (ANSI)

Don’t know what the deal is with high and turbo. As I said, other Sofirn lights I have are all in the ballpark of stated lumens.

So what’s it like?
Taking a look at the usable suspects we see.

C8, Sofirn TF84, Sofirn C8G

And again with everyone at attention.

Beam Shots
Here are those same three lights. As you can see the TF84 has a less well defined hot spot and a more gradual falloff into the spill area.
It’s much warmer that the other two. - A good thing.
Beam TF84

Beam C8 SST40

Beam C8G

As you can see, the other two put out a bit more light and the hot spots are, well, hotter.

In the Hand
The side switch is way easy to activate. I intend to leave it locked out.
With the side switch locked out, the UI is simple and very usable. The Main tail always turns on turbo. The Mode tail always turns on strobe (unless the light is already on). Then it cycles through the brightness modes. The number of modes depends on the group setting: Tactical or Outdoors.

I’ve often seen BLFs lamenting the absence of a light that just has basic functions and a single button to Turbo or Strobe. Well – here it is.

The switches are easy to find by feel and easy to manipulate. I like it.

The remote tail switch is another matter.

As you can see there are some small holes at the ends to mount the thing onto (something?). I think you could use zip ties or perhaps flatten out an M-Loc strip to mount it.
Mounting the switch with the cable toward the muzzle puts the large strobe contact closest to your off-hand.
To get to the main switch you need to get by this area. Not the easiest thing to do in reality.
I suppose you could try mounting the remote switch with the cable exiting toward the rear. This would put the main switch closer to the off-hand.
But this seems like a less than elegant solution.
Now I haven’t played with the TF84 in a mounted condition, so this is speculation so far.

So, is it a keeper?
Yes I think so.
What would I change?
Shorten the remote switch so that there is not so much space dedicated to the strobe function. Swap the cable to the other end so the main switch is closest to the off-hand position.
While built in charging is considered a must for many, I don’t think it should be used on a “tactical” light unless the port can be covered by something that has no possibility of coming off. This one is not that.

Don’t know what to make of the outputs. Wish they were closer to the rated output.

I really like the warmer color temp.
The UI, while different, is very usable. It just takes some getting used to.
Locking out the side switch makes the UI one of the best for a tactical light. I quite like it.

Well enough of my rambles…
All the Best,

Thanks for your detailed review, Jeff! We’re making a clearance for TF84, the promotion is still available, if you’re interested, feel free to contact me for a code.

Thanks for saving me some money. I would like another light for actual use on a weapon, but I’m not very tolerant of oddities for a weapon light, like the strong remote switch config.

I’ll wait an see what they come out with after they’re done w/ current clearance of this light.