Mares Magnetic Shaker — Black magnet-activated clip-on underwater noise-maker for signaling

The Mares Magnetic Shaker is a compact, magnet-activated noise-maker you clip to your BCD to get a buddy's attention underwater.

When voices and hand signals aren’t enough, a simple mechanical sound device helps cut through ambient noise and distance. The Mares Magnetic Shaker uses a magnet and internal ball bearing: flipping the magnetic end mutes the unit, while releasing it lets the ball strike the casing when shaken, producing a clear echoing rattle suited for underwater communication. Lightweight and corrosion-resistant, it stows on your gear so it’s ready whenever you need to signal or call attention quickly.

How does the magnetic mechanism control sound?

A built-in magnet at the end of the tube holds the internal ball bearing in place when engaged, preventing the ball from striking the casing and stopping continuous noise. When you remove or flip the magnet, the ball is free to move and create a loud echo as it contacts the inner walls while you shake it.

• Magnet blocks ball motion to mute the shaker.
• Releasing the magnet allows the ball to rattle for a distinct underwater sound.
• Simple on-off action avoids accidental signaling during entry or travel.

How will this fit into my dive kit and routine?

The Mares Magnetic Shaker is designed for clipped-on convenience and minimal bulk; it mounts to your BCD or harness so the shaker sits within easy reach. Its lightweight aluminum construction keeps overall kit weight low and it won’t take up valuable dry space in a pocket or pouch.

• Clip-on design for quick access on the BCD shoulder or chest strap.
• Slim profile lets it sit outside your suit without snagging.
• Aluminum body balances durability with minimal added weight.

What kinds of signaling situations is it useful for?

Use the shaker to attract attention during low-visibility conditions, to prompt a buddy when hand signals are missed, or to call for assistance in an urgent situation. It’s a non-electronic, maintenance-light tool that complements other visual or audible systems on the dive.

• Alert a buddy who’s out of sight or hearing range for voice commands.
• Supplement light or slate signals in murky water.
• Provide a simple audible cue during surface intervals or boat approaches.

How do I care for the shaker so it lasts through many dives?

Rinse with fresh water after each saltwater dive and allow the unit to air dry with the magnet disengaged. Aluminum and internal bearings tolerate repeated use, but routine rinsing and occasional lubrication (if specified by the manufacturer) will preserve function and reduce corrosion risk.

• Rinse thoroughly with fresh water after dives.
• Dry with the magnet open to avoid trapped moisture.
• Inspect clips and bearings for wear before long trips.

Who this is for: The Mares Magnetic Shaker is aimed at recreational divers, dive instructors, snorkeling guides, and research or rescue teams who want a dependable, low-maintenance audible signaling option. It’s especially helpful for divers who prefer mechanical tools over electronic devices, those who need a lightweight backup to visual signals, or anyone who wants an inexpensive, easy-to-use method to get attention underwater.