I've seen many different neutralizers on boats. I've been on boats with wooden baseball bats, aluminum baseball bats, ball pen hammers, sledge hammers, axes, 32 oz framing hammers, pistols, shotguns, police billy sticks, ugly billy sticks, bam bams, shovels, re-bar cut offs, even bare fists.
I had chartered a boat out of Key West when I saw the strangest of all skull crushers. The deckhand on the boat was an ex-golden glove boxer who loved to beat the living dodo out of a fishes skull. It was more fun watching him neutralize a fish than catching it. I caught a dolphin and when the fish hit the deck, the deckhand reached in his pocket and pulled out a pair of brass knuckles. He put his left hand around gill area and had the fish pinned to the deck. His right hand now with brass knuckles attached pounded the fishes skull numerous times.
I was amazed. The bill fishing was slow so I instructed the Capt. to target kingfish as there was plenty around. I don't really care to waste time catching kingfish, but I just wanted to see more skulls crushed. It was one of the most entertaining fishing trips I've ever been on. I'd hold the kingfish by the tail and the deckhand would stand back and jab the kingfish's head until it was almost removed. He loved it because it was a moving target. His right hand was bleeding from the sharp teeth.This went on for about two hours. Of course, I taunted the deckhand which made him really go crazy. It was a great day for the boxer. He told me that was the most fun he had ever had in his life. I felt the same way and gave him a great tip.