I think the Shark Shield probably works but probably not all the time and not on all species as well. Personally, I'd use one if I lived in certain counties since my mind goes certain places it shouldn't. Whatever psych-aid gets you in the water, use.
Defintiely a good idea if you're a free diver since there's no foam between you and the bottom row of teeth.
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Defintiely a good idea if you're a free diver since there's no foam between you and the bottom row of teeth.