^^ yes infact they are called....wait for it... Dive Knives. But according to my underwater naturalist class you aren't supposed to use them to kill things. Thanks PADI should have gone NAUI or even BSAC. I was wondering the same thing actually? Why didn't he just gut the sucker (no pun intended)?? So what if its a tool to cut ropes and entanlgements. I used to cut open clams and other shit just to see the other fish crowd around and feed. Its pretty cool.
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