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Moving away from the typical design for a single 18650 / 2x CR123 light, Fenix have come up with a nice compact, usable and simple everyday light, the E35.

The E35’s sleek design makes me rethink EDCing an 18650 powered light (for me a single AA or CR123 would be the biggest light I would EDC).





Initial Impressions:

The E35 arrives in the newer style Fenix blister packaging, which matches the E35’s no-nonsense approach.

Quality feels just as good as any Fenix light, so maintaining their great standards, and it seems just like a slightly overgrown single AA light.

No tail switch, instead having a side switch, initially makes you think this might be a simply twisty like many of the smaller EDC lights, but apart from giving a quick lockout, this is not a twisty.





What is in the box:

The outer packaging is Fenix’s newer blister style packaging. I could not get into this gracefully and I’m afraid the packaging looked like a child had unwrapped an exciting Christmas present after I had finished!



The E35 comes with lanyard, spare o-ring, and instructions (unfortunately no holster).



The E35





Taking a closer look and looking inside:

Looking into the compact head at the XP-E LED



The reflector looks somewhat ringy, but this is not at all noticeable in use.



Just like most small EDC lights, the head unscrews (rather than the tail) to insert the battery. The positive contact (shown here) and negative contact are both springs.



The threads are again Fenix Quality, anodised trapezoid, almost square cut and are flawless.



The tail has no switch and easily tail-stands unless you fit the lanyard which makes it unstable.



The one and only control, the electronic switch side button.





Modes and User Interface:

In keeping with its simple design, the E35 has a no frills interface.

To switch on, hold the button for 2s. The light will come on in the last mode used. To change modes press the button to cycle through High, Med, Low back to High etc.

To switch off, hold the button down for 2s.

Alternatively to switch off and lock out the E35, unscrew the head a quarter turn. However if you do this, tightening the head does not turn the light on, you still need to hold the button for 2s.



Batteries and output:

The E35 runs on any type of 18650 (I’ve tried protected, unprotected cells to cover the largest range of sizes) thanks to the two springs working with longer, shorter, flat top and button top.

It also runs on 2 x CR123 primaries, though the performance is not as good as on 18650. The E35 is shown here with 2 xCR123 for scale.



To measure actual output, I built an integrating sphere. See here for more detail. The sensor registers visible light only (so Infra-Red and Ultra-Violet will not be measured).

Please note, all quoted lumen figures are from a DIY integrating sphere, and according to ANSI standards. Although every effort is made to give as accurate a result as possible, they should be taken as an estimate only. The results can be used to compare outputs in this review and others I have published.

For the runtime tests though I am running the E35 on Fenix’s own 18650, the ARB-L2 which was charged using the Fenix charger the ARE-C1.

[TH]Fenix E35 output mode using ARB-L2[/TH]
[TH]I.S. measured ANSI output Lumens[/TH]
[TH]PWM frequency (Hz)[/TH]
	High (after cleaning the threads and contacts)
	253
	0
	Medium
	61
	0
	Low
	8
	0

Parasitic drain is a good 54uA meaning the ARB-L2 would take 5.5 years to run down due to parasitic drain. This is relatively negligible.

All output modes are free of any sign of PWM.

As with may Fenix lights, the highest output mode will step down to the second highest, and with the E35 this is after 32 minutes. For this runtime trace I reset the highest output each time it stepped down as you can see by the regularly spaced drops in maximum output (the first one caught me slightly by surprise, as after the first 30minutes I stepped away from the test rig for a few minutes thinking there would be no step down).

During the first hour the output is well regulated until the battery struggles to supply the power needed and the output starts to drop. Unlike many other Fenix lights though, the high mode did not then step down to the medium, instead it simply gave out as much light as it could. There was no sudden loss of light, it just got dimmer and dimmer.





In The Lab

NEW for Winter 2012 ANSI standards include maximum beam range. This is the distance at which the intensity of light from an emitter falls to 0.25lux (roughly the same as the lux from a full moon). This standard refers only to the peak beam range (a one dimensional quantity), so I am expanding on this and applying the same methodology across the entire width of the beam. From this data it is possible to plot a two-dimensional ‘beam range profile’ diagram which represents the shape of the illuminated area.

In order to accurately capture this information a test rig was constructed which allows a lux meter to be positioned 1m from the lens and a series of readings to be taken at various angles out from the centre line of the beam. As the rig defines a quadrant of a circle with a radius of 1m, all the readings are taken 1m from the lens, so measuring the true spherical light intensity. The rig was designed to minimise its influence on the readings with baffles added to shield the lux meter from possible reflections off the support members.

The distance of 1m was chosen as at this distance 1lux = 1 candela and the maximum beam range is then calculated as the SQRT(Candela/0.25) for each angle of emission.

In this plot, the calculated ANSI beam ranges are plotted as if viewed from above (for some lights there may also be a side view produced) using a CAD package to give the precise 'shape' of the beam.


Starting with the 5m range grid, the E35 has a narrow beam with decent throw.



Then zooming out to the 50m range grid showing the extent of the beam’s range. The smooth even hotspot pushes out to nearly 200m.





The beam

The indoor beam shot shows the dim spill and very well defined round hotspot.



The spill does not provide much noticeable illumination at any distance, instead the hotspot does have reasonable reach.





What it is really like to use…

The E35 has pushed my limits for EDC size up from single AA to this single 18650 light (just). Thanks to the simple layout, the E35 gives you good performance in a very compact package.

For EDCing I prefer to have a holster for the light so it is a little disappointing the E35 doesn’t come with one.

The side switch is very comfortable and natural to use. I found that having to wait the 2s to switch on and off was a little irritating. The delay is designed to prevent accidental operation, but it would be nice if Fenix could add a function that allows the user to set the button to immediate operation or delayed operation (as can be done in some lights such as Lupine’s flashlights).

The quality electronics keeps the parasitic drain to a minimum so that on 18650 it is negligible and on CR123 only a slight concern if setting this aside for long term backup purposes, but a quick quarter turn to lock out the power makes it safe to store.

Everyone has different limits for what they would EDC, and for me the E35 has expanded this limit. The beam is bright enough to ceiling bounce at close range where the hotspot might be too narrow, and the hotspot has a reasonable reach for the overall size of the E35.


Test sample provided by Rob of MyFenix (UK) for review.