Thetasigma
Flashlight Enthusiast
Hello everyone, these are my thoughts on Frelux's latest creation, the Synergy 2. This is a side by side format light that runs off a variety of cell options, custom made in Illinois, USA. This was purchased by me and I have no ties to Frelux.
Specifications:
-6061 anodized aluminum
-Samsung LH351D LED, 5000K, 90+ CRI
-Frelux driver, multi-voltage, constant current
-Frelux ramping UI
-Low voltage protection for both voltage ranges
-Physical reverse polarity protection
-Overtemp protection
-Weight (empty): 5.5 oz
-Dimensions (approx.) 95mm L x 43mm W x 21mm T
Price: $250 USD + shipping
Estimated runtimes and outputs:
Eneloop Pro - Low Output: 5lm
Eneloop Pro - Low Run Time: 200 hours
Eneloop Pro - High Output: 250lm
Eneloop Pro - High Run Time: 2 hrs 45 mins (tested)
Vapcell ICR14500 - Low Output: 5lm
Vapcell ICR14500 - Low Run Time: 90 hours
Vapcell ICR14500 - High Output: 500lm
Vapcell ICR14500 - High Run Time: 40 minutes
Vapcell ICR14500 - Turbo Output: 700lm
Vapcell ICR14500 - Turbo Run Time: 30 minutes
Driver: This is a highly capable constant current regulated buck/boost driver, where the batteries are in a parallel circuit, such that it can be powered off of 1-2 AA, NiMH, 1.7V Energizers, or 3.7V 14500s. It also offers the expected features of a quality light with low voltage protection, temperature protection, and reverse polarity protection. Switching between voltage ranges is automatically handled by the driver when switching cells. On 1.2-1.7V cells the output maxes out at ~250 lumens with a very long runtime, on 3.7V cells the output is bumped up and turbo is enabled.
This is what I would consider a holy grail of an EDC driver with the constant current output and wide voltage range which enables a wide range of options for powering the light off common cells and lithium-ion cells alike.
User Interface: The e-switch controls a simple and intuitive ramping interface. A click ON returns to the last used mode, holding the switch will ramp UP, releasing and holding again will ramp DOWN. A double click from ON or OFF will jump to turbo. Holding from OFF goes straight to moonlight.
In practice this interface is very simple to use and versatile. The ramping speed is a touch slower than some of the other contemporary ramping UIs, but faster than some of the older options like Bulk and LF2XT, this yields ramping slow enough to be precise but quick enough to not be annoying.
Reflector/Beam: This uses a 15mm SMO reflector that produces a fairly clean beam with minimal to no artifacts, with the Samsung’s large die size making a large spot with a wide spill. This setup yields a nice combination of throw and flood that makes it suitably versatile for an EDC role.
Clip: A point I consider vital for an EDC light, Frelux’s implementation is excellent. The clip is reversible so it can be mounted on either side of the light, is deep carry at nearly full depth, and has adjustable tension. The adjustable tension is a neat feature enabled by a slot in the clip where the main shaft and knob pass through, and the clip itself rides in its own dovetail groove, such that the tension can be set while tightening down the assembly knob. The tension ranges from loose for larger fabrics, pockets, etc, to extremely tight. The edge of the clip flush with the edge of the body in the groove is my preferred position for a firm tension on jeans pockets. An additional detail is Frelux has provided a clear sticker that can be mounted under the clip landing on your preferred side to protect the body from developing contact dents where the clip snaps against the body over long repeated use. The Frelux brand is also engraved into the clip.
Switch: This light uses an electronic switch on the driver, actuated by a sealed metal button. The tactile response is distinct but quiet, with a smooth feel. The switch is also moderately stiff, a nice change from many of the flimsy switches I’ve experienced in other e-switch lights. While the switch is stiff for an e-switch, Frelux has built a physical lockout option into the metal button. With the aid of the cutouts on the edge of the button, it can rotated clockwise and will not depress, twisting it counter-clockwise unlocks it for use. In practice this lockout implementation is excellent, and can be done without loosing grip of the light.
Build Quality: I have had the light completely apart and inspected thoroughly, machining quality is excellent throughout with good surface finish and tight fit. Assembly methods provide a solid location of parts repeatably, and ensure a good electrical path throughout the light. Solder-work on the driver and assembly is clean and precise. The anodizing process Frelux uses produces some of the best anodizing work of any flashlight, with an even, durable finish. The olive being used for the Synergy 2, is particularly stunning for fans of olive/green colors.
Note: Photo is stock from Frelux, I neglected to photograph mine while it was apart.
Grip: Being a side by side light running off AA sized cells, the light comfortable fills the hand, with the hourglass shape providing a very secure and natural grip even with the smooth finish. There are still some of the BFG grip lines as used on the S1 BFG, but they are more subtle this time around, providing an indexing point without being sharp or abrasive to the hand or pocket. The larger size of the Synergy 2 compared to the Synergy 1 makes the “pistol” grip very comfortable, putting the light in line with the natural flow of the wrist, and the switch under the index finger for easy control, all while being a very secure grip position. With the clip on the right side for right side draw, I did not experience any hotspots as the clip is devoid of sharp edges and well finished. Similarly with the clip mounted on the left side while still in a right hand grip, the clip does not provide any hotspots either.
Battery cap: A challenge of the side by side format, Frelux’s solution is simple with a main-shaft that runs the length of the light with a pair of retaining nuts holding the front and middle sections of the light together in normal use, along with the body pieces interlocking at their sealing surfaces. The assembly knob threads on to this shaft as well to secure the battery cap. Replacing the battery cap after changing batteries like the Synergy 1 still requires some dexterity, I recommend compressing the battery cap on to the body with one hand and threading the knob on with the other hand, but the clip being retained in the groove simplifies it a bit over the loose clip present in the Synergy 1. A note on threading the assembly knob, it should start very easily and smoothly, if it is difficult to start it is likely crooked and would cross-thread, like any small thread application take a bit of care here.
Overall, while requiring a bit of dexterity I think the simplicity and the deep-carry reversible and adjustable clip it enables is worth the any minor inconvenience a battery change entails.
Conclusion: At present, the features and execution of the Synergy 2 lead me to conclude that this is without doubt one of the best EDC lights made to date, with an unmatched level of versatility and utility mixed with excellent build quality, simplicity of use, and at a price from a small USA maker that remains competitive with higher end production lights and wipes the floor of most custom lights, in an unusual but excellent compact form factor.

Specifications:
-6061 anodized aluminum
-Samsung LH351D LED, 5000K, 90+ CRI
-Frelux driver, multi-voltage, constant current
-Frelux ramping UI
-Low voltage protection for both voltage ranges
-Physical reverse polarity protection
-Overtemp protection
-Weight (empty): 5.5 oz
-Dimensions (approx.) 95mm L x 43mm W x 21mm T
Price: $250 USD + shipping
Estimated runtimes and outputs:
Eneloop Pro - Low Output: 5lm
Eneloop Pro - Low Run Time: 200 hours
Eneloop Pro - High Output: 250lm
Eneloop Pro - High Run Time: 2 hrs 45 mins (tested)
Vapcell ICR14500 - Low Output: 5lm
Vapcell ICR14500 - Low Run Time: 90 hours
Vapcell ICR14500 - High Output: 500lm
Vapcell ICR14500 - High Run Time: 40 minutes
Vapcell ICR14500 - Turbo Output: 700lm
Vapcell ICR14500 - Turbo Run Time: 30 minutes



Driver: This is a highly capable constant current regulated buck/boost driver, where the batteries are in a parallel circuit, such that it can be powered off of 1-2 AA, NiMH, 1.7V Energizers, or 3.7V 14500s. It also offers the expected features of a quality light with low voltage protection, temperature protection, and reverse polarity protection. Switching between voltage ranges is automatically handled by the driver when switching cells. On 1.2-1.7V cells the output maxes out at ~250 lumens with a very long runtime, on 3.7V cells the output is bumped up and turbo is enabled.
This is what I would consider a holy grail of an EDC driver with the constant current output and wide voltage range which enables a wide range of options for powering the light off common cells and lithium-ion cells alike.
User Interface: The e-switch controls a simple and intuitive ramping interface. A click ON returns to the last used mode, holding the switch will ramp UP, releasing and holding again will ramp DOWN. A double click from ON or OFF will jump to turbo. Holding from OFF goes straight to moonlight.
In practice this interface is very simple to use and versatile. The ramping speed is a touch slower than some of the other contemporary ramping UIs, but faster than some of the older options like Bulk and LF2XT, this yields ramping slow enough to be precise but quick enough to not be annoying.
Reflector/Beam: This uses a 15mm SMO reflector that produces a fairly clean beam with minimal to no artifacts, with the Samsung’s large die size making a large spot with a wide spill. This setup yields a nice combination of throw and flood that makes it suitably versatile for an EDC role.

Clip: A point I consider vital for an EDC light, Frelux’s implementation is excellent. The clip is reversible so it can be mounted on either side of the light, is deep carry at nearly full depth, and has adjustable tension. The adjustable tension is a neat feature enabled by a slot in the clip where the main shaft and knob pass through, and the clip itself rides in its own dovetail groove, such that the tension can be set while tightening down the assembly knob. The tension ranges from loose for larger fabrics, pockets, etc, to extremely tight. The edge of the clip flush with the edge of the body in the groove is my preferred position for a firm tension on jeans pockets. An additional detail is Frelux has provided a clear sticker that can be mounted under the clip landing on your preferred side to protect the body from developing contact dents where the clip snaps against the body over long repeated use. The Frelux brand is also engraved into the clip.

Switch: This light uses an electronic switch on the driver, actuated by a sealed metal button. The tactile response is distinct but quiet, with a smooth feel. The switch is also moderately stiff, a nice change from many of the flimsy switches I’ve experienced in other e-switch lights. While the switch is stiff for an e-switch, Frelux has built a physical lockout option into the metal button. With the aid of the cutouts on the edge of the button, it can rotated clockwise and will not depress, twisting it counter-clockwise unlocks it for use. In practice this lockout implementation is excellent, and can be done without loosing grip of the light.

Build Quality: I have had the light completely apart and inspected thoroughly, machining quality is excellent throughout with good surface finish and tight fit. Assembly methods provide a solid location of parts repeatably, and ensure a good electrical path throughout the light. Solder-work on the driver and assembly is clean and precise. The anodizing process Frelux uses produces some of the best anodizing work of any flashlight, with an even, durable finish. The olive being used for the Synergy 2, is particularly stunning for fans of olive/green colors.
Note: Photo is stock from Frelux, I neglected to photograph mine while it was apart.

Grip: Being a side by side light running off AA sized cells, the light comfortable fills the hand, with the hourglass shape providing a very secure and natural grip even with the smooth finish. There are still some of the BFG grip lines as used on the S1 BFG, but they are more subtle this time around, providing an indexing point without being sharp or abrasive to the hand or pocket. The larger size of the Synergy 2 compared to the Synergy 1 makes the “pistol” grip very comfortable, putting the light in line with the natural flow of the wrist, and the switch under the index finger for easy control, all while being a very secure grip position. With the clip on the right side for right side draw, I did not experience any hotspots as the clip is devoid of sharp edges and well finished. Similarly with the clip mounted on the left side while still in a right hand grip, the clip does not provide any hotspots either.


Battery cap: A challenge of the side by side format, Frelux’s solution is simple with a main-shaft that runs the length of the light with a pair of retaining nuts holding the front and middle sections of the light together in normal use, along with the body pieces interlocking at their sealing surfaces. The assembly knob threads on to this shaft as well to secure the battery cap. Replacing the battery cap after changing batteries like the Synergy 1 still requires some dexterity, I recommend compressing the battery cap on to the body with one hand and threading the knob on with the other hand, but the clip being retained in the groove simplifies it a bit over the loose clip present in the Synergy 1. A note on threading the assembly knob, it should start very easily and smoothly, if it is difficult to start it is likely crooked and would cross-thread, like any small thread application take a bit of care here.
Overall, while requiring a bit of dexterity I think the simplicity and the deep-carry reversible and adjustable clip it enables is worth the any minor inconvenience a battery change entails.


Conclusion: At present, the features and execution of the Synergy 2 lead me to conclude that this is without doubt one of the best EDC lights made to date, with an unmatched level of versatility and utility mixed with excellent build quality, simplicity of use, and at a price from a small USA maker that remains competitive with higher end production lights and wipes the floor of most custom lights, in an unusual but excellent compact form factor.

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