The LRI Proton is a very interesting light. It has 6 white LEDs in a circle surrounding a single red LED. Using circuitry similar to the LRI Photon Freedom, the LEDs can be turned on, either white or red, and adjusted to a large variety of output levels. Four blink modes are also selectable. A single switch controls all of the modes. The Proton is powered by a single AA battery and includes a substantial pocket clip.

Body:

The body of the Proton is made of Type III anodized aluminum and has ridge rings around the head and body for grip. Attached at the tailcap and hanging down the side is a large stainless steel pocket clip which can be removed if desired. On the side just below the head is the single rubber-covered switch that accesses all of the different Proton modes. At the tail is a riveted-in-place-type post where the lobster claw swivel keychain is attached.

Bezel/Head:

The head consists of a screw-off bezel ring which holds a slivered plastic reflector in place in front of the LEDs with a little formed cup for each LED. The LEDs themselves are embedded in epoxy that has glow powder added, and as a result when the LEDs are off you can see the front of the light glowing in the dark. There is no lens window in front of the reflector to protect the plastic reflector or the LEDs, but the LEDs are fairly well recessed in the face of the light

Output:

The white light produced by the 6 white LEDs produces good color rendition. Each LED creates a beam that has a slight bluish tint in the center and a slight yellowish tint around the edges. During normal use the tinting is not really noticeable and the overlapping beams create a very nice wash of light. The red LED makes a smooth and vivid red beam. Blink modes, whether red or white, are very eye catching and include SOS and slow, medium and fast blink. In addition to the documented modes, there are two secret modes (how to access them is listed in the Switch section, below). One allows you to turn on all of the LEDs at once which gives a pleasing warm tint (from the red LED) to the white LED beam, and the other allows for greater battery conservation in red-only mode.

All throw readings are in Lux at one meter. The numbers in parenthesis are for comparison in the Comparison Charts.

   
Beam at one meter at target center: White LEDs only, Secret White+Red mode.
Red LED beam not shown due to difficulties in photographing.

Runtime Plot:

Optimal runtimes are encountered when using lithium AA cells or NiMH cells. Alkaline batteries do a fair job but will only give about 45 minutes continuous runtime. Both runtimes completed on bright white mode.

Runtime completed with Energizer L91 AA brand batteries. More information on runtime plots is available HERE.

Runtime completed with Rayovac brand batteries. More information on runtime plots is available HERE.

Runtime Plot with NiMH 2300mAh energizer:

Runtime completed with Energizer brand batteries. More information on runtime plots is available HERE.

Switch:

The switch is a multifunction single click switch, operating in a manner similar to that found on the Photon Freedom.

When you first get the light it will be in "demonstration" mode. Press and hold the switch until the light turns off (about 20 seconds). After that you can access all of the modes. Here's how they work:

Off -> Press and release: white LEDs on high -> Press and hold: variable dimming starting high, release when it gets to the level you want -> Press and release: Off

Off -> Press and hold: Red LED variable dimming starting low, release when it gets to the level you want -> Press and release: Off

To access the blink functions: Press and hold (red) or click (white) so that the light is on. Press and hold until the light starts blinking for Low, Medium, High strobes and SOS in that order, repeating. Release when it gets to the mode you want. Press and release to turn off.

Off -> Press and release rapidly several times -> Momentary only mode, only works when pressing the switch - for 3 sec. use or less at a time. Press and hold until light turns off to take it out of this mode.

To access the secret "all white LEDs on including the red LED" mode: Press and hold till red turns on and keep holding. Release when the first blink mode is reached (this is the second quick flash you see when the red LED is brightest). Turn it off. Turn it on with a click and all LEDs will be on until you use the red mode again. If you press-hold to turn the light on in red-only mode, the "all LEDs mode" will be turned off again and only the white LEDs will turn on with a click of the switch.

There is also a secret "50% Red" mode, available only in the red LED setting that will help conserve battery life. If you press-hold to turn on the red LED, and immediately release the button as soon as the red LED turns on, you can then press-hold the button to ramp up the LED in 50% mode. This appears almost as bright as the regular red LED only mode, but uses less power.

One thing that does bother me about the switch is the design of the rubber cover. The rubber cover overlaps the hole the switch is in. As a result, the edges of the rubber cover can get caught and lifted. It looks to me like there will be a fairly high probability that the switch cover will eventually get caught on something and tear or pull completely out.

Seals / Water Resistance:

The light is water resistant, and has a sealed head and an O-ring seal at the talicap.

If it gets wet inside, just disassemble as much a possible without tools and let it dry before using again.

Ergonomics:

The Proton is very small and easy to carry clipped to a pocket or just dropped into a pocket. You can clip it to your keychain as well. It is very easy to operate but without the pocket clip attached it can be a little difficult to locate the switch since it is almost flush with the body. The body texture provides sufficient grip.

Size compared to a common 2AA aluminum light

Batteries:

A single AA sized battery powers the Proton and you can use alkaline, NiMH or lithium AA 1.5V cells. Inside the Proton you will see two gold plated bent tabs. One is at the base of the head and one is in the tailcap. These tabs are rather inflexible and although they make good contact with the battery, they make it difficult to put the talicap on without crossthreading it. Also, LRI put a very short band of rather fine threads (three circles of threading, max) on the tailcap which results in an even greater chance of crossthreading. I am concerned that the threads may be worn and/or damaged fairly quickly. After only a couple of battery changes the tailcap threads and O-ring became thoroughly coated with a fine aluminum powder from wear to the threads, this despite the fact that I cleaned the threads and put liquid Teflon lubricant on them after the first battery change. I really think the band of threads should have been wider (more threading), the threads more substantial, and a spring should have been used in either the talicap or head for contact instead of the relatively inflexible bent metal tabs.

Another light manufacturer tried the bent-tab design and had to switch back to springs after many complaints that the tabs just don't work well as a resilient contact.

I did find that I was able to make the tailcap behave a little better by pressing the tailcap tab down into the tailcap hard with my thumbs. This released some pressure off the bottom of the battery and made it easier to screw in.

To change out the batteries: unscrew the tailcap, drop out the old cell, place in a new cell observing proper polarity. Reattach the tailcap (carefully) and you're ready to go.

Accessories:

Included with the light is a very substantial belt clip (attached) which can be removed and replaced with a spacer to fill the gap left by the clip. It appears that you should use the spacer to remove the clip, and vice versa, by putting the two prongs of the spacer against the two prong of the clip and pushing the clip out. Fat chance. Take a piece of nylon cord and catch it under the clip at the 90 deg angle and pull really hard to get the clip off. Since the spacer does not have any protruding parts to grab, I think it's unlikely you'll be able to remove it after it is inserted. I left mine out.

Note that with the pocket clip attached to the tailcap, the clip puts pressure on the side of the body when you try to reattach the tailcap after a battery change. This in concert with the very stiff battery contact in the tailcap makes the tailcap try really hard to crossthread and can make reattachment of the tailcap fairly difficult without damaging the threads. To remedy this it may be necessary to pull the clip outward away from the body just a little so that it only makes very gentle contact with the body. That way the clip is not putting pressure on the body as the tailcap is being screwed in.

Also attached to the light is a lobster-claw clip at the tailcap.

What I Liked: Water resistant, Impact resistant, Good battery life, Bright, Lightweight, Many modes of operation

What I Didn't Like: Uncertain of tailcap thread durability due to fine threads and short length..

Picky Little Things: Internal battery contacts too stiff - required manual adjustment. Pocket clip presses against the body when screwing in the tailcap, forcing it off center and it tries to crossthread - you may need to bend the clip a little; switch cover can catch on things; no lens.

Conclusions: Overall the LRI Proton is a good little light. The fact that it can use common AA alkaline cells for power means that you'll almost always be able to find batteries for it, but you can use lithium AA for longer runtime and better cold-weather use or NiMH for a more environmentally friendly approach. The ability of the light to be dimmed to almost nothing, or start out with almost no light in red mode, allows for a great range of uses. Full power mode, whether red or white, provides sufficient light for most personal-use tasks. The blink modes provide a safety factor and the glow-in-the-dark bezel allows the light to be easily located in the dark. I would prefer to see a spring contact for the battery, a lens for the front, a possible redesign for the switch cover, and more substantial threads for the tailcap, but these are just my personal preferences. I like everything else about it and the light is very usable as-is. The Proton has possibly the most versatility of any light I've reviewed.

Quick Facts Table: