The Bends Mender is designed to deflate the air bladder of a fish caught in deep water. Some fishermen prefer the through the mouth method as a way to deflate the air bladder.
A fish can arrive at the surface bloated--especially when caught from deep water. In effect, the fish has "the bends". If released, it cannot descend into the water properly unless the air bladder is deflated. Use your Bends Mender to save the fish's life...
The Bends Mender comes with a protective cap, and built in reamer to clean the needle after each use. Bends Mender makes deflation easy with explicit directions.
Method 2 is recommend for beginners.