Answer: concertinas

AnswerCrossword Clue
CONCERTINASAccordion relatives
concertinasOpening or closing in multiple folds
concertinasCONCERTINA
concertinasA small musical instrument, typically polygonal in form, played by stretching and squeezing between the hands, to work a central bellows that blows air over reeds, each note being sounded by a button