It is wise to test your gear before you find yourself relying on an unknown performance and tempting Mr. Murphy to show what happens when you assume. I tested this mirror and two others:Ultimate Survival Technologies StarFlash Signal Mirror andUltimate Survival 2x3 Star Flash Signal Mirror . I was looking for inexpensive sight-grid aimable mirrors in the approx. 2-inch by 3-inch size for various kits and each vehicle. I am posting companion reviews of all three mirrors in each of their Review sections. Pros: +++ Excellent reflected light performance (tested in first place, although pretty close) +++ Very good aiming performance (easily took first place) + Small lanyard hole in corner + Protective plastic case (can also be a con) + Floats + When aiming, the grid appears to accurately show the spot where it is really placing it + Slip case comes with product for additional protection of reflective side Cons: - Plastic outer layer can be scratched (came in distant second place) - If sonic welds on plastic case break, protective case can fill with water and reduce reflection performance Granted my sample size is one, the performance of this mirror was excellent compared among the tested mirrors, taking first place. I tested all three brands of signal mirrors at 15 yards and 25 yards. At 15 yards the reflected light spot of this mirror was very tight, bright, and consistent. At 25 yards, this mirror's reflection shows a circular spot ~8 inches in diameter. Wanting an indicator of longer distance performance, I tested in a field aiming from a 3-foot berm to an assistant on the horizon 200 yards away (verified by laser range finder). This test was conducted with the sun high (no clouds) and slightly behind the user (at approx. 1330 in summer). This is a difficult test for a signal mirror (and a great way to stress the tool's performance limits) as the sun is at a very wide angle (>90 degrees) to the signalling target. Starting with the technique with the hand held outstretched, the spot in the star grid was pretty easy to find when aiming to the horizon. The time and effort to get the spot on the target and keep it there was better than the other mirrors (which can be critical in a time-sensitive opportunity), taking an easy first place. My assistant reported this mirror reflected slightly more light compared to the UST, again taking first place. I also performed a dunk test, first verifying the mirror floated. The mirror spent 30 minutes in 9 inches of water, and when released, it slowly but surely floated to the top. The sonic welds of this brand new mirror did not allow any water to creep in (but the welds have not been stressed tested from regular carrying). Protective cases (esp. when scratched) and water fogging inside only add barriers to efficiently putting reflected light energy on a target. I did lightly scratch in one corner with the tip of a sharp knife and this mirror took second place, scratching with a little more effort than the third place mirror, and with the UST resisting significantly better. It is a good idea to use the provided slip case or a small piece wrapping to protect a signalling mirror from scratches on the reflective side. Packaging states "Glass reflection surface for superior flash distance", which probably explains its first place performance. Packaging also states "Waterproof & Break-Resistant acrylic case", "Floats", "(C)2008 Coghlan's Ltd, Winnipeg, Canada R3T 4C7", "Sight-Grid Targeting Mesh Made in USA", and "Signal Mirror Made in Japan". From my amateur astronomy experience, I know Japanese optics and glass are very highly desired. The mirror has usage instructions on the rear and I weighed it at 1.01 ounces on my calibrated scale. Conclusion: While this is not quite 5 stars, I wish I could give it a fraction more than four. This Coghlan's mirror came in a close first on reflection performance across 200 yards, easily came in first on reflected light spot characteristics, and easily first in ease of aiming. As long as the sonic welds on the protective case hold up, this Coghlan's mirror will not fog inside. TheUltimate Survival Technologies StarFlash Signal Mirror has a slight advantage in size (biggest difference when packing is in thickness), weight, and much better scratch resistance. TheUltimate Survival 2x3 Star Flash Signal Mirror performed in a very distant third. On a final note, I have noticed this signalling mirror is available in almost every store that has a camping section as Coghlan's is very widely distributed.
