These are musical instruments.
“The Bell of Opening is a unique item you encounter during the Quest (along with your role's...Bell of Opening
“A magic harp is a tonal musical instrument, and one of the two harps. If it has any charges left...Magic harp
“A tooled horn is a tonal musical instrument, and the only non-magical horn. It can be used to...Tooled horn
“A bell is a musical instrument. It does not play notes; its function is to ring. Bells are often...Bell
“There are two overall categories of musical instrument in NetHack: tonal instruments, which are...Musical instrument
“A bugle is a tonal musical instrument. It can be used to play the passtune to enter the castle...Bugle
“A magic flute is a magical tonal instrument, and can be used to play the passtune. Improvising...Magic flute