Nice inexpensive gadget
I have bought, used, and replaced a number of these 4 function whistles, both the black (adult) and the yellow (kid) styles. I haven’t noticed any difference between the two, except that the yellow is much easier to find when dropped.
I have gotten these for myself, my wife, and my two small children (ages 4 & 6). We clip these on to our kids’ belt loops, zipper pulls, or packs whenever we go hiking. A whistle is no substitute for keeping the kids in sight, but it’s a nice backup just in case. We’ve taught them that three toots means come help me, and when they hear two toots, it means we are trying to find them. To help alleviate the temptation to blow it for fun while we hike, we usually let them make one loud blow at the beginning and/or end of a trail. They are beginning to learn compass basics. The magnifying glass is functional, and my kids like playing with it. The gadgets give a few minutes of entertainment for them both on the trail and in the car.
When leading a youth group on a backpacking trip, I bought these for everyone participating (black for adults and yellow for teens). Everybody in the group was instructed that these are to always be on their person - when they go out of sight to relieve themselves, hunt for wood, hang the bear bag, collect water, etc. - it is to always be attached just in case. We had no problems, but it helped me as the group leader feel a bit more secure, plus all the teens thought it was neat that they got a new piece of gear.
This compass only gives general direction (certainly not detailed enough for orienteering), but can be a backup for your primary compass.
The thermometer is very basic and gives only very general readings at increments of 5 degrees Fahrenheit and 2 degrees Celsius. On two of mine the mercury separated in the thermometer.
When dropped in the mud, these have been easy to clean. It is pealess, which I prefer, as it means I don’t need to worry about a ball getting stuck due to dirt or internal ice.
It is relatively light, but if all you need is a whistle, you can get lighter and smaller.
The clip is nice for attaching to packs or belt loops. The greatest problem with these whistles is the low-quality chain-link that connects the clip to the whistle. I have had four of these break, twice resulting in the loss of the whistle (which can result in a crying toddler). I lost one whistle when hiking through a blue berry patch. The whistle had been attached to my pack, but a few miles later all that remained was the clip and half the chain. It is cheap, so no big loss, but I did feel badly about a piece of plastic now littering the woods somewhere. Plus, since I lost it, I couldn’t use it to scare off a bear I encountered the next day; fortunately yelling worked.
After losing that whistle, I bought a Silva four function whistle, because it has a string lanyard instead of the chain-link. Both the Coghlan and the Silva are made in Taiwan with the same patent numbers. The only differences that I can tell are: the color (the Silva is grey), the price, and the lanyard string vs. chain-link and clip. The string has been much more dependable, but it would have been just as easy to attach string to the cheaper Coghlan. However, for small children a clip is better than a neck lanyard, as a lanyard around the neck can pose a strangulation hazard.
I would recommend this to a friend as a cheap gadget, while noting the above limitations. I would also recommend using a string lanyard with mini-biner (or a key ring with a mini-biner) in place of the chain-link. I would recommend the cheaper yellow (which is easier to see when dropped) rather than the black. They make for great stocking stuffers. I would especially recommend this for children and teens, as I’ve experienced them really liking this gadget. Plus if you or your child loses it, it is no major loss to your wallet.
I bought two, and own an old one.
1. They fixed the week chain. These units are now delivered without the chain; the split ring on the hook is now attached directly to the device (see photo). Generally the instrument is secure, robust, and strong
2. The compass is accurate enough (on the ones I have) to generally account for declination, and to find your general way back to your party. All three of mine indicate the same.
Tip: The compass must be held level to swing freely. When you are tired and cold and your brain is not working well, use extra discipline to force yourself to hold it carefully, to let it swing freely to tell you the way to safety.
3. The whistle is loud. It can blast your ears. But you must blow hard.
4. The thermometers are inaccurate. Two of my three indicate the same. One is as much as 5 degrees off (see photo). Add that to the 5 degree resolution of the scale. It is being sent back.
REI, How long do we have to put up with the inaccuracy of cheap toys in our outdoor instruments? 40 years ago, pocket thermometers (as well as compasses) were accurate and reliable enough to always be within 1 or 2 degrees total. I remember seeing them in stores, all displaying the exact same numbers. It can be done. But across all your product lines, there does not seem to be a single one with the accuracy that can be consistently achieved with careful manufacturing.
Toward that end, please list, in the specs of all instruments, the comparative accuracy in +- degrees. (Your people can determine this quickly by comparing a batch of them side by side and with an accurate control instrument. Then take the deviation + and - from the control. Or ask the factory.) Instruments should be accurate enough to easily compare their reading numbers with other persons with other instruments. Then the numbers can be shared within a party, and also help teach our youth something worthwhile. For instance, if one person reads 73 degrees and another has 80 degrees, it doesn't work.
In outdoor use, especially when things are going wrong, it helps a great deal to be able to depend on our equipment. For example, are we having a freeze, or not? And sometimes, a few degrees can mean the difference between life and death.
I know these are low priced products. But an accurate one would sell for more.
Tip: If the liquid separates in a thermometer, usually a lot of patient tapping of the lower end onto a hard surface can bring it back together.
Another Tip: In this unit, there is a vent hole into the area of the thermometer bulb. Blowing the whistle will blow warm air onto or near the thermometer and change the reading.
The thermometer is mounted inside a sturdy plastic capsule so it won't break. But this means the thermometer must be given a while to get to ambient air temperature.
May God bless you.