I use this whistle for bike rides. Little bells ...
341118
I use this whistle for bike rides. Little bells are worthless for people with ear buds. This whistle will catch drivers in cars from turning in front of you.
I use electrical shrink tubing to prevent teeth from crunching on steel. Used this whistle in the Merchant Marine to catch the attention of crew about to do something dangerous. It is very loud!
2740850
I ride a lot on dedicated non-motorized paths in northern Michigan. Occasionally, the need to pass other bikes or navigate through pedestrian traffic arises. I found after a year or so that (1) voice warnings when approaching pedestrians and some bikers often startled them - in rare instances even causing them to move in the wrong direction and into my path (2) I was getting tired of giving frequent voice warnings. With a bell, most people seem less startled and more understanding of the situation. An added advantage is that if you are going around a "blind" corner you can sound the bell to warn people you might not even see.

This bell has three advantages which I like: (1) it's loud enough, (2) it's small enough, (3) the one I purchased blends in nicely with my bike's trim and controls,  and so is very unobtrusive. I initially mounted it on the left side thinking I didn't want it on the same side where I do most of the shifting. That was a mistake. When navigating in close quarters I prefer to have my left hand on or near the front brake lever.  Trying to operate the front brake and bell at the same time proved difficult. In addition, the bell sets-up better on the right side where it was likely intended to go. Works great now.

Please bear in mind that this bell will ring loudly in any position you mount it in. It doesn't know "upside down" from "inside out".  However, if mounted "right side up" on the handlebar you may increase the risk of damaging it should you invert your bicycle for servicing.  Since I often invert my bike to clean and lube the chain, I instinctively placed the bell so that it is lower than the handlebar when riding. In this position it works well on the right side. I suspect some of the questions about whether this is a "right-sided" or "left-sided" bell relates to this issue. :))

Minor issue:  When I pulled the bell off to reposition it a tiny hex-nut inside the mounting hardware dropped out. I wasn't even aware of its presence originally, but it had apparently loosened up during use. After reinserting this nut I found its threads had become stripped and it wouldn't accept  the screw that tightens the mount down on the bike's handlebar. Searching my shop for a while,  I came up with an identical nut that worked well.  Presto.  We're back in business.

Edited on August 12, 2017:  I've lowered my original rating from "4" to "3" after using this bell for about 2 months. The reason for the lowered rating is that the bell has begun functioning erratically. The sounds emitted now range from a loud "ding" to only a muffled "thud". Usually, it's somewhere in between those two extremes. There's no way to know in advance what to expect. Since this isn't a toy, but rather a safety device, I'm disappointed. To put things in perspective:  I ride almost daily in the summer and sound the bell perhaps  a half-dozen times per ride. So it's had a good workout over the past couple months.  For the price, I can't complain. But I'll need to replace it soon, and most likely will try a different brand.
4263572
The rubber end is way better than the plastic tips, I have a tendency to chew on my whistle. However, it could be a bit louder, I feel I really need to put some effort into my blow ;)
1612597
I can either put up with incessant pointless barking or try to do something about it. The whistle does seem to have some effect on these dogs even though they are four city lots away. I have to be outside or have the window open, and blow the whistle as hard as I can. This is a nice, sturdy brass whistle. There's an adjustment screw that isn't well explained in the instructions, but I guess there's not much to it. I tried the dog whistle iPhone app, but it's harder to give the dog immediate feedback because you have to unlock the phone and navigate to the app before you can use it. I keep the whistle on a lanyard and wear it when the dogs are typically barking... 8 AM, 11 PM, or whenever a squirrel walks by... Note to neighbors: You're welcome.
2995873
I recently purchased this UST JetScream Whistle . This whistle is a screamer. I have no doubt about being heard when I need to be. It cost a little more than other whistles but it is well worth the price. It's small, sturdy, floats, no little rattling pea and it can be heard from far away. I plan on buying a couple more. Don't forget Made In USA.
110633
I use this while mountain biking with friends. Provides enough sound so that if two people are trail riding behind you, the last person can still hear the music. The back rubber flap needs to be closed to get good sound quality, so charging and playing is inadvisable. The mount isn't the best, and at full tightness on the handlebar, it still tends to flop upside down. I took a spill off of a wood brige above some marshy grass, and the speaker got a little wet. It still worked fine.
The bluetooth works 98% of the time, but sometimes it seems to disconnect for no reason.
I would recommend if you want to listen to music while biking, but still want your ears open for other bikers. Other bikers will also be alerted to your presence. I would say this is a good buy.
217403
Love this little speaker! I attached it to my bike rack and run a cord to my smart phone which sits on my handlebars. I love biking and bumping some tunes. Speaker sounds great especially for the price. Light drizzle has not affected the speaker but I do remove it during hard rain (if I get caught out there).
4405151
I really like the sound of the D whistle.  When playing a song or just the scale the "C" note was more in tune on this brand of whistle than on the brass whistles that I have.  The tone is very clear and more mellow.  The little case is great to carry both the C and D whistles.
1590672
Cute ... cute .... cute!  Sounds like old-fashioned bike bell.
1282452
I like to listen to music when I ride, but headphones are illegal and frankly, not very smart.  A speaker like this one lets you hear the music and the cars.  There's only one problem, they are frequently difficult to attach to the bike and they are useless in the rain.

Not this guy!  The suction cup just folds up and fits into the air vents in a bike helmet, just fold two sides of the suction cup together and insert into any long air vent on the top of your helmet.  The plastic used for the suction cup is grippy and isn't going anywhere once inserted, as it unravels and sticks to the inside of the air vent, not like a suction cup but lust from the force of the thing putting itself back into shape.

Just in case it wasn't fully waterproof (I don't know why I worried - you can use it in the shower), I put a sandwich baggie over the top and secured it with a rubber band.  The thing pairs effortlessly with my cell phone (all I did was turn it on, turn on my cell phone blue tooth and it was found right away.  Any radio app plays through it.

Sound is very good, though not super high fidelity and not super loud, but since the thing is right on top of your helmet, it's fine.  Light weight so it'd not uncomfortable to wear.  About the size of a hockey puck, but only weighs a few ounces.

So now I can ride with tunes in the rain.  A++ for this purpose.
4903751
Not something use use all the time, but when needed, it's great!  If someone can't hear this whistle, they're the one's in need of help.
Super cheap insurance/saftey equipment. Even in your car or on construction site. Want to get someones attention, just a slight toot will do it.
4850912
This horn is great for a child's bike. Makes the perfect fun noise and the kids love it.
2345713
This little bell is loud enough for people to hear you coming but small enough to still look cool on your mtn. bike.  As a side note, they accidentally shipped to wrong address, BUT send me another one. Thank you.
1827133
Mirrycle Incredibell Brass Duet Bicycle Bell (Chrome Plated)
This little bicycle bell is awesome!  While riding my bicycle on busy pathways I needed a pedestrian alert system. Checked this out on Mirrcle's website where they have audio samles of all of their bells. Sounded loud enough and was small enough (some of their bells are quite large). The price on Amazon was a better deal, so ordered the chrome plated bell from them - Prime got the bell to me almost immediately!  When I took it out of the packaging and tried it out, I was really happy with the volume/sound of the dual "ring" - it will definitely alert people/pets to my approach, and with a pleasant sound. BTW, used he bell on New Year's Eve to "ring" in the New Year -loud and clear. I highly recommend the Mirrycle Incredibell Duet Bicycle Bell - check out their other awesome bells too.
4125675
Super loud whistle! I purchased a replacement after I lost the first one on a camping trip. I would rate 5 starts because the first one I had worked flawlessly and I loved it. The 2nd one still works great, but I think it's a slight lemon. I have to blow into it harder to get it to sound right  unlike the first one which was pretty damn loud from just a small blast of air. So im gonna give it 4 stars since it still works.
1097024
This is a solidly constructed bike bell. This will grab the attention of people jogging on the trail you're riding on. I have also noticed that even people with headphones on can hear this bell. The tone it emits is very pleasantly tuned. I find the people I warn on my approach are much more receiving of the nostalgic sound than yelling "Rider on the left". I no longer get shown the middle finger or get disparaging remarks when out riding my bike. This really changed my perception of the joggers on the multi-use trails as I get all smiles now.
1500457
Whistle works well. I haven't taken it out yet to test the rest of the features on a camping trip. Will be adding this to our bags for emergencies.