...How to use it? Well, firstly i get the fish under control. This normally ends up with my left hand solidly holding on to the fish's gills. If the fish is large, my legs will be wrapped around the body of the fish. The ikijimi spike is then pulled from its holder and inserted a short distance behind its eyes, from the top. (same place you'd despatch it, with a knife) The rule is to draw a equilateral triangle between its eyes, with the apex of the triangle showing you where the brain should be. A solid push into the head, should despatch the fish as quickly and humanely as possible, with very lttle danger to yourself.
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