Warning: pic heavy, as usual.
The P0 is a new model in the 4Sevens (now Foursevens) Preon family of AAA-based lights. The P0 is a particularly tiny stainless steel light, with a floody beam. Let's see how it stacks up
Manufacturer Reported Specifications:
- LED: Cree XP-E Cool White
- Max Output: 25 Out-the-front (OTF) lumens
- Two Output Modes:
- Low: 0.24 OTF Lumens, 120 hours
- High: 25 OTF Lumens, 1.5 hours
- Material: Stainless Steel
- Lens: Optical-grade glass lens with anti-reflective coating on both sides
- Water resistance: IPX-8
- Battery: One AAA, included. Please do not use lithium-ion cells in the Preon P0 as it will destroy the light (see voltage range to select acceptable batteries for this light).
- Operating voltage range: 1.0V - 1.5V
- Length: 2.2 inches
- Diameter: 0.5 inches
- Weight: 0.46 ounces
- Included Accessories: Split-ring for keychain attachment, One AAA battery
- Operation: Insert the battery with the positive side (+) toward the head. To turn it on, tighten the bezel (head) fully. The Preon P0 will turn on when the bezel is tightened, and turn off when the bezel is loosened. To switch between High and Low output, turn the Preon P0 off and then on again within 1 second. If the Preon P0 is turned off for 2 seconds or longer, it will revert back to Low.
- MSRP: ~$23
Packaging is a small plastic box with clear top and cut-out foam to securely hold the light. The light comes with a keychain split ring already attached, and a free Duracell alkaline battery. The manual is printed on the back of the box. There was no extra o-ring with my sample, but I believe they may be included on later ones.
From left to right: Duracell AAA; 4Sevens Preon P0, Preon 1, ReVo; Titanium Innovations Illuminati; Klarus Mi X6; Lumintop Worm SS.
4Sevens Preon P0: Weight 13.0g (with keychain clip), Length 55.0mm, Width 12.6mm (bezel)
4Sevens Preon 1: Weight 15.3g (with keychain clip), Length 75.6mm, Width 14.0mm (bezel)
Olight i3: Weight 13.2g, Length: 71.9mm, Width (bezel): 14.0mm
Illuminati Aluminum: Weight 13.9g (with keychain clip), Length 68.8mm, Width 14.0mm (bezel)
Klarus Mi X6: Weight 16.2g, Length 72.9mm (battery installed), Width 12.8mm
The P0 is tiny! Weight is in keeping with others in this class, due to the stainless steel construction (i.e. most of the others are aluminum, which is lighter).
Build is fairly unique. Stainless construction feels sturdy. The light doesn't have knurling, but the brushed finish over most of the light helps with grip.
Screw threads are fine, but feel solid (i.e. very little play on my sample, better than most lights this size). Light works by tightening the head against the body. There is no spring in the tailcap the light relies instead on a small raised post. There is a foam disc around the positive contact button in the head, to stabilize the battery and insulate the electronics.
The P0 has a built-in split-ring attachment point on the tail of the light, which allows both tailstanding and hanging straight. There is an integrated magnet on the tail, which is strong enough to hold the light horizontally off any metal surface.
The "reflector" seems to be a conical-shaped piece of GITD plastic. It is not really designed to collect the light and focus very much it seems to be used mainly for its glow-in-the-dark properties. I would expect a very floody beam, with little defined hotspot.
The P0 is very straightforward - tighten the head and it comes on in Lo. Do a rapid twist off-on and the light advances to Hi.
And that's it. You can keep doing repeatedly cycles by loosen-tighten twists of the head. Wait a few seconds before re-activating the light after turning off, and it returns to default Lo.
There is no memory mode, the light always defaults to Lo.
For a more detailed examination of the build and user interface, please see my video overview:
Video was recorded in 720p, but YouTube defaults to 360p. Once the video is running, you can click on the quality icon and select the higher 480p or 720p options. You can also run full-screen.
The P0 appears to be current-controlled. I could detect no sign of PWM at either level.
There is no strobe mode either.
All lights are on Sanyo Eneloop 1xAAA NiMH, about ~0.75 meter from a white wall (with the camera ~1.25 meters back from the wall). Automatic white balance on the camera, to minimize tint differences.
Ok, my standard test bed really doesn't show you much. Part of the issue is the lower output of the P0 (i.e., only 25 reported lumens on Hi). But the main reason you can't see anything is the camera depth of focus the P0 puts out a much wider (and even) spillbeam than any of the other lights.
To better show you what it looks like, here is the P0 up close against a wall, compared to a typical 1xAAA light (both are probably ~10 cm away from the wall)
As you can see, the P0 has a wide and even beam (i.e., very floody). A traditional reflectored light tends to have a bright hotspot and corona, with narrower overall spill.
All my output numbers are relative for my home-made light box setup, a la Quickbeam's flashlightreviews.com method. You can directly compare all my relative output values from different reviews - i.e. an output value of "10" in one graph is the same as "10" in another. All runtimes are done under a cooling fan, except for any extended run Lo/Min modes (i.e. >12 hours) which are done without cooling.
I have recently devised a method for converting my lightbox relative output values (ROV) to estimated Lumens. See my How to convert Selfbuilt's Lighbox values to Lumens thread for more info.
My summary tables are reported in a manner consistent with the ANSI FL-1 standard for flashlight testing. Please see http://www.sliderule.ca/FL1.htm for a description of the terms used in these tables.
Max output seems bang-on in my testing, very close to the reported 25 lumen spec. Obviously, not much throw here - this light won't light anything up beyond a few meters.
Lo output is more complicated to describe please refer to my discussion after the runtimes below.
Runtimes are good on Hi, with very flat regulation on all battery types. The L92 energizer lithium cell was particularly long-lasting, but even alkaline does fairly well for its class.
For Lo mode runtimes, I am doing something different below. Here, I am showing estimated Lumens (converted from my lightbox's relative output values). The reason for this is that the output varies a fair amount by battery type and over time, so it's easier to compare in actual lumen estimates.
The L92 lithium run settles down after 15 mins into a regulated level very close to the reported 0.24 lumen spec (although it starts out more than twice that brightness). However, the alkaline and Eneloop NIMH battery runs have different initial outputs, and show a gradual decay that is not perfectly flat. Note that output is considerably lower on NiMH.
Here's is a longer timescale, to show you the regulation patterns better:
As you can see, the L92 lithium levels off a little above 0.20 estimated lumens. Alkaline and Eneloop NiMH are contiuing to drop over this time frame, though.
UPDATE FEBRUARY 17, 2011: Here is an even longer time scale, now up to 24hours. Note that the alkaline run stabilized around 12 hrs into the run, at a relatively low level (i.e., I estimate just below ~0.04 lumens).
To summarize, here are my estimated lumen output values for the three battery sources, at different times:
UPDATE FEBRUARY 19, 2012:
I am not a fan of doing low mode runtimes on lights that have expected multi-day durations. There reason for this is that small differences between emitters (most especially Vf) can result in drastic differences between samples. So, unless you have multiple samples (from multiple batches), it is very hard to get a good feel for what a typical runtime would be.
With that caveat in mind, below is what I have gotten to date on my one sample. Note that the runtimes are approximate, as I am not running these continuously in my lightbox (i.e. I just check in every couple of hours to see how they are doing).
Sanyo Eneloop: battery fully drained between 36 and 44 hours (i.e., a little over 1.5 days)
Duracell Alkaline: battery fully drained between 48 and 52 hours (i.e., a little over 2 days)
Energizer L92 Lithium: battery fully drained at 66.5 hours (i.e. a little under 3 days)
Again, don't shoot the messenger here - your sample could vary significantly. I only present my results above to add to what others are finding - they should not be taken as indicative of "typical" performance. Without multiple samples to test, I can make no comment about expected runtimes or the natural variance (which I expect can be a factor of 2 or more). Again, the last thing I want to see posted here is "Selfbuilt proved it only runs 2 days on Lo" ...
Small head-twist lights with raised negative contact posts always have the potential to be battery crushers. I recommend you do not over-tighten the head, and periodically check your batteries to ensure they are not getting dented.
I had some intermittent flickering on my sample, on all battery types. This was usually resolved by loosening and re-tightening the head. I also experienced "flaky" mode switching on occasion (i.e., the light would suddenly jump from Lo to Hi shortly after initial activation). I suspect both of these issues are due to the pill loosening up slightly. You can remove the foam cushion and tighten the pill with fine tweezers (but make sure to restore the foam, see comments below)
The light is very small, and may be hard to use one-handed for those with larger hands (especially if it gets wet and slippery).
The battery tube is narrow, and you may have to smack it upside down against your hand several times to get the old battery out.
There have been reports of the light not working with Sanyo Eneloop NiMH cells (or their "Duraloop" rebranded equivalents). Worse, there also several reports of permanent failure of the P0 when this has been attempted. Note that I used Eneloop cells extensively in my testing, and have not experienced any issues on my sample.
The reported issues are believed to be due to the wider positive button head (anode) on these Eneloop cells. The foam disc may prevent contact with the contact plate in the first case, resulting in inconsistent activation. In the second case, the cell may be shorting out against circuit components located near the center of the contact board (at least, that is the popular theory here on CPF). I have measured the diameter of several types of 1xAAA batteries, and can confirm the Eneloop cells have a wider anode button than other battery types.
Again, I have done a lot of Eneloop testing in my sample, and did not experience any issues. But it is a potential concern, so you may want to hold off using Eneloop-style cells until we get greater clarity from 4Sevens. At a minimum, I strongly recommend you do not remove the foam cushion in the head, as it should provide some insulation and protection.
The P0 is a very distinctive little keychain light. Probably the smallest 1xAAA light I've ever seen, it also has one of the floodiest beams I've come across.
Let's start with the build extremely petite, but solid with the stainless steel construction. I personally like the look and feel (although find it a bit small for my hands). Screw threads are firm with little play. The keychain split-ring can freely rotate, allowing both tailstanding and a straight hang. The integrated tailcap magnet is an interesting feature keeps the light firmly attached to metal surfaces (but will also attract other metal items in your pocket).
Note however that the light lacks a tailcap spring, so you should take care not to over-tighten (i.e., may dent your cells). There are also potential concerns about shorting out the light when running on Eneloop NiMH (likely due to the wider width of the anode button on these cells). I look forward to more info from 4Sevens on this issue. The only problem I experienced was some inconsistent mode switching, but this can be resolved by tightening the pill under the foam cushion.
The beam is quite interesting, as it has a fairly sharp demarcation along its outside spillbeam edge (i.e., doesn't just gradually fade away like most lights). It reminds me of an aspheric lens coupled with a 5mm emitter (i.e., no defined hotspot, more of a spotbeam effect) although with a broader overall beam width in this case. Any way you slice it, the P0 has a fairly unique profile. Those who clamor for true "flood" should find what they want here.
The GITD "reflector" is a cute feature although it is more a conical light collector than a reflector. It does provide a fair amount of glow after the light has been on awhile.
The selection of output levels is somewhat unique, with an ultra-low "Moonlight" Lo mode and a relatively mid-level Hi mode. But thanks to the wide spillbeam, the Hi mode may not seem as bright as even the 25 lumens suggests (i.e., the light has no real dedicated throw, so is only suitable for up-close use).
Runtimes certainly seem reasonable for the output levels - I'm particularly impressed with L92 lithium cells in this light. I'm still performing Lo mode runtimes, but note there is some variability in output levels and regulation patterns between different battery types at this level. While L92 lithium eventually levels off at ~0.15 estimated lumens within a few hours, alkaline takes a good 12 hours or so to level off at a much lower output (just below ~0.04 lumens in my testing).
The P0 fills a very specific niche in the 1xAAA market (i.e. ultra-tiny, with a wide and sharply defined "floody" beam). Hopefully the apparent issue with Eneloops will soon be sorted out. If you are a true flood fan in this class of light, the P0 could be what you are looking for.
Preon P0 was supplied by 4Sevens for review.