The day somebody creates a fail proof shark repellent is the day that person becomes a billionaire. I mean with absolute certainty,  “you will never be attacked by a shark thanks to this item or product” levels of confidence. I think the statistical leeway on said product would have to be in the realm of assuring 100% results – or maybe even higher. Now tell me a product deters sharks nine out of ten times and my first question automatically becomes “ok so what do I do on the tenth time?” 90% is pretty good. I guess. I can still count on one hand how many times I’ve knowingly shared ocean space with a shark. One time I willingly jumped in the water with a bunch of them (no it wasn’t in a cage and yes they were big) and it was awesome. And who knows how many times I (and you) have swam around with no idea that an animal or two were curiously cruising around? That number might be scary. But luckily, and thankfully, I have a 100% safety rating to this date. Thankfully. But now you’ve put that last 10% in my head – that one in ten chance – and honestly it’s the only 10% I can think about now. Ignorance really is bliss.
The inventors of the Shark Shield feel pretty good about their 90%. With the help of a $300,000 grant from the Western Australian government’s Applied Research Program they developed a technology that creates a three-dimensional electrical waveform, causing muscle spasms in a shark’s short-range electrical receptors. The only way for the sharks to make the spasms stop is to move out of the waveform’s range. It’s been developed and tested over the course of two and a half years and turned into a tailpad/antenna system that can be installed on a surfboard. The antenna itself is actually a decal that runs along the bottom of your board and slides over the rail, connecting to the tailpad module that you screw in. As of this July these will be on the open market, offering piece of mind (nine out of ten peaceful minds, to be exact) to anybody with the system installed on their board.
There are actually several pieces to file in the plus column here. Tom Carroll helped develop and test the system so you aren’t paddling around with a massive battery and antenna sinking your board. I like Tom Carroll. He’s a really awesome human. So that’s a plus. And groups like Sea Shepherd are stoked on the FREEDOM + Surf  because it deters sharks without harming them. I think sharks are rad and shouldn’t be hurt. That’s another major plus. And according to the University of Western Australia Ocean Institute, the people who independently and scientifically tested the Shark Shield, it “deterred a shark interaction nine out of ten times.”
I’m still not sure if that’s one addition to the minus column or nine points in the plus column.