Ultrafire WF-502B 3W Cree Flashlight, retail $18.45 (www.dealextreme.com...)
Manufactured by (Unknown)
Last updated 08-22-13

The Ultrafire WF-502B 3W Cree Flashlight is a sturdy, smallish-medium-sized flashlight that uses a 18650 rechargeable cell (battery) and a high-powered Cree LED near the bottom of a stippled ("orange peel") reflector.

It comes in an almost all-aluminum body that has several; knurled (texturised) bands for grip, and also has a sturdy spring steel clip fastened to the body with not one, but two screws.

Its light engine features a Cree XR-E P4 three watt LED.


To use this flashlight, feed it first (see directly below), and then you can go light up the side of a toliet factory several blocks away.

Press the rubberised tailcap button until it clicks and then release it to turn the flashlight on.
Repeat the same action to turn the flashlight off.

There is no momentary or signalling mode available when the flashlight is off, however, you can blink the Ultrafire while it is on by partially depressing the tailcap button. If you don't mind the backward or reverse feeling of this, you can blink the flashlight this way.

To feed the Ultrafire, unscrew & remove the tailcap, chuck it into the nearest open-pit gadolinium mine, and wait for a piece of heavy machinery to run over & destroy it...O WAIT!!! YOU'LL NEED THAT!!! So just set it aside instead.

If necessary, tip the used 18650 Li:ION rechargeable battery out of the flashlight and into your hand.

Insert the battery into a charger designed for 18650 cells; and charge as directed.

Slide the newly-charged 18650 cell into the Ultrafire's barrel, orienting it so that its button-end (+) positive goes in first (toward the flashlight head), and firmly screw the tailcap back on.
Aren't you glad you didn't kick that tailcap into the open-pit mine now?

Current usage measures 855mA on my DMM's 4A scale.
This current was measured when powering the Ultrafire WF-502B flashlight with two CR123A primary (disposable) lithium cells - this type of cell is often found being used in cameras and high-powered flashlights.

The Ultrafire WF-502B flashlight appears to be quite durable, but it would not be fair to perform "The Smack Test" at this time because I do not have an 18650 cell handy and I'm kind of "fudging it" with a pair of CR123A cells which fit rather poorly - smacking this flashlight now would almost certainly cause it to stop working.

Water-resistance appears to be quite good at worst - it passed "The Suction Test" with no problems whatsoever.

There are three bands of knurling (crosshatch-haped texturising) on the tailcap, barrel, and just below the bezel. These help with retention (the ability to hold onto the flashlight when your hands are oily, cold, or soaked with diet Mountain Dew, chocolate milkshake, bird poop, coffee, pee, or water) - that should not be much of an issue at all.

Intensity is somewhat higher than expected - especially for an LED.

Beam photograph on the test target at 12".
Measures 3,730,000mcd on a Meterman LM631 light meter.

Beam photograph on a wall at ~10 feet.

Those rectangular graphic things in the upper right quadrant of this photograph are marquees from:

Sega ''Star Trek''
Atari ''Tempest''
Venture Line ''Looping''
Jaleco ''Exerion''

upright coin-op arcade video games from the 1980s.

And those colored graphics near upper-center are my "Viva Piņata" posters.

Beam photograph inside a house (aiming at the front door); est. range 50 feet.
This photograph was taken at 5:39am PDT 08-30-08.
Zoom was used on the camera, which is why it doesn't look like 50 feet.

Spectrographic plot
Spectrographic analysis of the LED in this flashlight.

Spectrographic analysis
Spectrographic analysis of the LED in this flashlight; newest (01-13-13) spectrometer software settings used.

Spectrographic analysis
Spectrographic analysis of the LED in this flashlight; newest (01-13-13) spectrometer software settings used. Spectrometer's response narrowed to a band between 445nm and 455nm to pinpoint native emission peak wavelength, which is 451.180nm.

The raw spectrometer data (comma-delimited that can be loaded into Excel) is at http://ledmuseum.candlepower.us/43/ultrafir.txt

USB2000 Spectrometer graciously donated by P.L.

ProMetric analysis
Beam cross-sectional analysis.
Image made using the ProMetric System by Radiant Imaging.

Product was purchased on the DealExtreme website on 08-05-08, and was received on the morning of 08-22-08.

Product was almost certainly made in China.
A product's country of origin really does matter to some people, which is why I published it on this web page.

UPDATE: 09-13-10
I have given this light to my aunt; therefore I no longer have it at my disposal for future analyses or comparisons -- and the dreadful "" icon will now be appended to its listings on this website.

The Spider Fire LED Flashlight that I gave her early this year has partially failed, so I simply exchanged it for this one.



    PRODUCT TYPE: Medium handheld flashlight
    No. OF LAMPS: 1
    BEAM TYPE: Medium spot w/dim corona
    SWITCH TYPE: Pushbutton ("reverse clicky" on/off on tailcap
    BEZEL: Metal; LED & reflector protected by glass window
    BATTERY: 1x 18650 Li:ION rechargeable battery
    CURRENT CONSUMPTION: 855mA (2xCR123A primary cells)
    SUBMERSIBLE: Yes, to shallow depths at minimum
    WARRANTY: Unknown/not stated


    Star Rating

Ultrafire WF-502B 3W Cree Flashlight * www.dealextreme.com...

Do you manufacture or sell an LED flashlight, task light, utility light, or module of some kind? Want to see it tested by a real person, under real working conditions? Do you then want to see how your light did? If you have a sample available for this type of real-world, real-time testing, please contact me at ledmuseum@gmail.com.

Please visit this web page for contact information.

Unsolicited flashlights, LEDs, and other products appearing in the mail are welcome, and it will automatically be assumed that you sent it in order to have it tested and evaluated for this site.
Be sure to include contact info or your company website's URL so visitors here will know where to purchase your product.

WHITE 5500-6500K InGaN+phosphor 
ULTRAVIOLET 370-390nm GaN 
BLUE 430nm GaN+SiC
BLUE 450 and 473nm InGaN
BLUE Silicon Carbide
TURQUOISE 495-505nm InGaN
GREEN 525nm InGaN 
YELLOW-GREEN 555-575mn GaAsP & related
YELLOW 585-595nm
AMBER 595-605nm
ORANGE 605-620nm
ORANGISH-RED 620-635nm
RED 640-700nm
INFRARED 700-1300nm
True RGB Full Color LED
Spider (Pirrahna) LEDs
True violet (400-418nm) LEDs
Agilent Barracuda & Prometheus LEDs
Oddball & Miscellaneous LEDs
Programmable RGB LED modules / fixtures
Where to buy these LEDs 
Links to other LED-related websites
The World's First Virtual LED Museum
Legal horse puckey, etc.
LEDSaurus (on-site LED Mini Mart)

This page is a frame from a website.
If you arrived on this page through an outside link,you can get the "full meal deal" by clicking here.