Put on the end of your crook to lower the pitch, as an alternative to buying a longer crook. If you are playing in a hot room or concert hall, the temperature will raise the pitch of your bassoon. Some bassoons play sharper than others naturally too, and some reeds are sharper in pitch than others. This crook extension can help bring the pitch back down if you are having problems playing too sharp in some situations.
Equivalent to moving to the next number crook - 1 to 2, 2 to 3, etc.
Made of brass, knurled for easy fitting and removal. Just push fit on with friction, so no need to adjust. It should work for most crooks without a problem.