This is a replacement tuning key for the Starter Harp. The handle is made of hard maple and the square opening fits the tuning pins on the Starter Harp. Not all harp tuning pins are the same size. This tuning key is only guaranteed to fit the Starter Harp and not other harp makes and models.
While the Starter Harp comes with a tuning key, it’s a great idea to order a few extras to keep places like your car or your grandma’s house so you are never accidentally without it when you want to play your harp on the go.