Equipment Review: Thyrm Switchback 2.0 Large (on Fenix PD-35)

I cannot recall where I first saw the Thyrm Switchback.  It may have been on a light utilized by Aaron Cowan of Sage Dynamics in a video, or perhaps adorning one of the lights used by the guys at Practically Tactical, who always seem to get all the “cool-guy” gear first.  I do recall that I first saw a ring utilized on a flashlight during the Advanced Individual Tactics class taught by Paul Howe of Combat Shooting and Tactics.  The ring in this case was a simple metal ring attached to the clip of a Surefire flashlight (used by a police officer who was attending the class with me). 


I do not know much about Thyrm except that they seem to make a few niche products that get high praise from all of those who use them.  When I first saw the original Switchback—which is essentially a ring that fits over the rear of the flashlight—I was definitely intrigued.  However, the fact that neither the original “large” version nor the “backup light” version fit any lights that I then owned—or planned to own—had me keeping the little gizmo in the back of my mind, but that was about it.

What most intrigued me about the Switchback is the little nub on the ring that allows the user to push forward, which in turn pushes the tailcap switch against the rest of the user’s fingers/knuckles, activating the light.  This allows the user to assume a more “normal” firing position, supporting the pistol with the hand that is utilizing the light.  It is a neat concept.

Earlier in 2018, Thyrm released a 2.0 model in their “large” category, and this new model, in addition to having numerous improvements, also fit a flashlight I already owned.  After completing the A.I.T. class referenced earlier, I (and many other students who attended that class) purchased the Fenix PD-35 flashlight, which came with the unofficial Paul Howe seal of approval (he told me he had mounted one to an AK on a Larue mount with no ill-effects to the light under recoil).  I have now owned this light since late 2015 and continue to sing its praises.  There is a reason this light appears on our “Recommended Gear” page.  Even almost 3 years ago this light was sold as a 960 lumen light that has many other features I enjoy (adjustable brightness separate from the tailcap switch being one of them), not the least of which is its price-point. 

While I have enjoyed the features of the PD-35, its fairly large size for a civilian EDC item had it relegated to a backup and home-defense role in recent months, usually replaced by a Streamlight 1L-1AA Dual Fuel light in my pocket, which is much smaller.  However, since acquiring a Thyrm Switchback for the Fenix light, these two flashlights have reversed roles, as I now find it worth it to carry the PD-35 everywhere. 

The Switchback

The Thyrm Switchback 2.0 arrived packaged like this:


In the packaging is the Switchback itself, a rubber O-ring, and a metal washer.  Depending on which light you mount the Switchback, you may have to use the washer, the O-ring, both, or neither.  In the case of the PD-35, the washer is all that is necessary.

The Switchback retails for $19.99.  I believe I purchased mine from an eBay seller just because I had some extra money in my PayPal account at the time and figured “Why not?”  It is available in 3 different colors (black, urban grey, and tan….I went with black).  In its new 2.0 version, in addition to being able to fit on a multitude of other lights, the Switchback also features a slightly reshaped “ring” (it’s not a true circle, but more like an oval or elipse), a beefed up clip, and a “breakaway” feature which allows the ring to open up if something or someone twists the light in your hand.  This feature essentially keeps the user from having his finger broken if the light is twisted in the hand while the ring is being used (note:  the breakaway feature does not break the ring, but merely opens it.  Once “broken”, it can then be put back into its original configuration). 


Installation of the Switchback is really quite simple.  First, remove the tailcap from the flashlight:


 Next, fit the Switchback over the back of the flashlight.


Next, install the metal washer on top of the back of the batteries (again, as noted earlier, some lights might need the washer, others the O-ring, others both, and perhaps other will need neither).


Next, install the tailcap.  That is all there is to it. 



Using the features of the Switchback is also very easy.  One would typically, in “search” mode, carry it in this fashion, with the ring around the index finger and the thumb on the tailcap switch:


Flipping the light by utilizing the ring around the index finger places the light in this position:


Pushing forward on the little “nub” on the outside of the ring with the thumb cantilevers the tailcap switch onto your middle finger, activating the light:


A modified firing grip can then be achieved, shown here with a Glock 26.

Left side:


Right side:


Additional Benefits

Having a ring near the tailcap of the flashlight provides some additional benefits.  First, when the light is inside a pants pocket (clipped to the edge or just loose in the pocket), acquiring a grip on the light is easy, because once the index finger finds the ring, it can fish it out using the ring and does not require the entire hand to get a grip on the light while still inside the pocket.  Second, the ring allows retention of the light while the rest of the hand is needed for other tasks, such as reloading a pistol, clearing malfunctions, accessing a knife or less-lethal tool, opening doors, etc.  All of these benefits come with the trade-offs of a slightly bigger footprint due to the ring (though the ring is quite flat, so if you can fit the flashlight into your pocket without the ring, it should still fit WITH the ring) and about $20 out of your wallet.

Final Thoughts

This HAS to now rank as among the best $20 I have spent on gear.  Having the Switchback attached has made my PD-35 “viable” again.  I used to consider it more of a specialized tool, to take with me only when I was going someplace obviously dark, like a movie theater.  For the last three months, however, it has truly been my everyday carry light.  It is now in my pocket at work, walking the dog (which is when I practice flipping the light from one position to another), to the beach at night on a recent trip so I could avoid becoming dinner for an alligator on the way back to our rental unit, etc.  Its utility when combined with a handgun has removed any thought I might have had about mounting a light to my concealed carry pistol, as I can now achieve a viable two-handed grip with a handheld light.  Though larger than the Streamlights I have also used, I regard the trade-off as worth it given the power of the light and its utility with the Switchback.  In short, this is, in my opinion, a great little piece of kit, and I highly recommend it.  Accordingly, it can now be found on our Recommended Gear page.

As always, thanks for reading.  If you have any questions or comments, please post them here or on our Facebook page, as we always welcome civil discourse.  Please note that some links above will take you to our Amazon Affiliate page.  Purchases you make going through that portal support us here on the blog with a slight percentage of each sale at no cost to you.  Keep in mind that we run this page with our own money with no sponsors, so we always appreciate your support.  I can be reached privately at


6 thoughts on “Equipment Review: Thyrm Switchback 2.0 Large (on Fenix PD-35)

  1. Good review. Note for any users running the Fenix UC35 V2.0…the only way I could get the light to work with the Switchback mounted was to use the included washer/spacer and to remove the Fenix factory O Ring from the base of the threads. I’m guessing this might affect the overall waterproofness of the light. Which is kinda a bummer.


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