Chad Patti was treading water just off the coast of Florida when he was suddenly lunged at by the shark.
The 30-year-old can be heard screaming in this clip that he shared on Facebook after miraculously emerging unscathed.
"You never know when you'll become the prey," he said in his post, before adding: "Not a scratch on me."
"Luckily he only took my fin and not my life," he wrote.
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