Mares Magnetic Shaker - Underwater Scuba Diving Safety Signaling Noise-Making Device

I have seen a bunch of variations of the noise makers, but I was drawn to this one the most. My only concern was if it would rattle too much unintentionally. When on land, it does rattle quite often so this made me worry. But rest assured, underwater it works perfectly. It is very loud and easy to use.The one thing that might not be obvious is that you have to "reset" the shaker after use. After using it, the ball bearings are still loose, so you have to invert the shaker so that it reengages the magnets and locks in place (you will hear a snap).Some might ask why you need something like this for diving. While I think it is obvious, let me share a story with you. In my first dive trip ever I went to the Galapagos. On my final dive, our dive master took us deeper than we were supposed to at 30 meters (I was only an open water diver certified for 30 feet). I wasn't aware, because I was using rental equipment that was not working (another big mistake). I was with a group of 6, just a few feet away from my buddy when suddenly lost vision. Everything went black, but I was still conscious. I tried to grab my buddy and signal for help, but I was in the back and even though I was just a few feet away, no one realized something was wrong. My dive buddy was following someone else (who she thought was me), and the dive master must have not been keeping tabs on me.I ended up being left alone for 3 minutes under water completely blind. Fortunately, I figured out that I had a mask squeeze, cleared my mask, and restored my vision (albeit very blurry and seeing double). I couldn't find my group and had to surface. The boat directed me towards my group, and I rejoined them later on. To my surprise, no one even realized I was gone and only realized when I appeared.While a lot of things went wrong here, having a noisemaker would have quickly brought attention to me and prevented the situation from escalating. That is just one example, and I am sure there are many more. That is why I have a noisemaker for me and for my buddy, and would dive without it now.

Makes a noticeable noise when you shake and magnet prevents accidental noises when you don't need it. Stow easily on BC.

I was hesitant to purchase this, as it's hard to know what to expect. The shaker does not make much noise above water (unless you are purposely shaking it, and a jingle hear and there), but works really well underwater when you are trying to shake the device. This device made me feel more secure as a diver, simply giving me a way to get ahold of my buddy or divemaster if needed (especially when we get distracted and find ourselves spaced out). It was all really helpful to get someones attention when you wanted to point something out - especially when the group is ahead of you. The noisemaker did not scare away fish, however, we didn't use it when we were surrounded by sharks, so I'm not sure if it would scare them away or not. Great $30 for comfort. The name Mares is starting to wear off after 6 dives, but it doesn't seem to be impacting the noisemaker itself.

Very sturdy manufacturing, which is great, and also sounds very loud, so it is great for the purpose I bought it. The only detail is that the magnet is very strong and you actually need to agitate it strongly to release the balls and make it rattle.But other than that, it serves very well the purpose. Recommended!

After years of using a air integrated underwater alert, got tired of them leaking (even though I regularly soaked them in a vinegar solution to remove corrosion) and started looking for something simple that wasn't expensive and not tied to air. This shaker is the ticket for me. I should give some advice. The magnet is VERY strong so the interior noise maker stays firmly attached to it and does not rattle accidentally. However, this means that you have to shake it vertically under water to release the interior ball from the magnet for it to work and it does take some strong shakes to release it. Once it does, shaking it works really well. I used it yesterday on a dive and the sound carried very well. I am a 71 year old woman and if I can shake it hard enough to disengage the magnet, I would think that most can. I do recommend experimenting with it before diving to get a sense of how hard you need to shake it to disengage the magnet.

Its a great device and the magnetic part is a nice addition. I used to have a non magnetic device. The problem with it is that it makes annoying noise as you moved it around. The magnetic addition holds it so that it does not sound when you move it around. When time comes to use it, you just shake it to break the magnetic hold, and from that on it works like a regualr shaker. In my openion, a shaker of any type is a must from divers. It's the least expensive way to get your buddy's attention.

They are a bit hard to get sounding, but sound loud enough when needed.

Yes, this is expensive, but it is sturdy and works quite well. If anyone needs to know, it is 3/4 inch by 6.25 inch, and weighs exactly 4 ounces (feels heavier than that) The supplied string is cheap and should be replaced with a proper stainless steel ring and/or good lanyard.