These guys seem to have created an ankle band that uses magnets to repel sharks

Sharkbanz are an easy way to add peace of mind to the everyday ocean swim, surf, or snorkel, but make no mistake: the science is real. To create this breakthrough protection from sharks, we partnered with the leading shark repellent scientists at SharkDefense. They’ve put this patented magnetic technology to the test for over 10 years against the predatory shark species most responsible for attacks on people, including Bull Sharks, Blacktips and Tiger Sharks. Most shark attacks occur in murky, shallow waters off the coast where there are a high number of swimmers and sharks sharing the same space. These unprovoked “hit and run” attacks are the most common type, and Sharkbanz are an excellent defense against them. As the shark approaches a person wearing Sharkbanz, magnetic waves coming from the band disrupt its electro-receptors, and it quickly turns away. For the shark, the sensation is similar to someone shining a very bright flashlight in your eyes in a dark room, and while this deters the shark, it does not harm it. Stingrays are also repelled by Sharkbanz, and the technology does not affect other marine life. Sharkbanz use no chemicals, batteries, or electricity to deter sharks, ensuring simplicity in use, storage, and durability. Just strap it on when you arrive at the beach, and let your fears fade away. Our company pledges to donate a percentage of profits to ocean conservation groups with targeted efforts to pass legislation and affect measurable, positive change on our worlds oceans. You can rest assured that with every Sharkbanz purchase, another sea turtle, dolphin, or shark will be safe from harm. We like our toothy aquatic neighbors, but just prefer they keep their distance. While there is no 100% guarantee against an encounter, Dr Rice says that by wearing Sharkbanz, the risk is significantly reduced. There’s a fine line between bravery and stupidity, so don’t cross it and provoke a shark by attempting to test this technology yourself. They are wild animals and don’t take kindly to people with bad manners. Respect the animals and they will respect you.