Do you find you are playing too sharp? This is the item for you.
Just slot this brass crook extender onto your crook using the specially design grip section and it will lower your pitch (about the same as buying the next longest crook). This saves buying an expensive longer crook and is ideal if you find you are going between hotter and colder areas where pitch may vary.
This crook extender will fit all bassoon crooks, just gently put it onto the end of your crook and friction will hold it in place.