The Hohner ROCKET HARP Harmonica Model M2013BX-G is a diatonic harmonica in the key of G. This harmonica, manufactured by Hohner, is a high-quality instrument suitable for various musical genres, especially folk and world music. Its model number, M2013BX-G, indicates the specific design and key of this harmonica, making it a reliable choice for musicians looking for a versatile and well-crafted instrument.