Howard's bassoon is a musical instrument that only appears in the episode "New Fish in Town" and belongs to Howard.
The bassoon is a woodwind instrument that is in the double reed family, and has its music usually written in bass clef, but occasionally can reach the treble clef as well. It is most commonly found in orchestras, ensembles, and concert bands.
Howard's particular bassoon is colored metallic blue and has a long row of keys with a curved and silver bocal coming out from the body of the instrument.
Role in episode
When Squidward is having a conversation with Howard, Howard mentions that he plays the bassoon. He and Squidward head inside of his trailer where they perform their own instruments together with Squidward using his clarinet.