Hohner 3P572BX Hot Metal 3 Harmonica Value Pack, Keys C, G, A The 10-hole, diatonic Hohner 572 Hot Metal Harmonica Smooth and comfortable plastic comb, brass reeds, and stainless steel covers 572 Hot Metal is similar to Hohner's Old Standby harmonica 3-pack contains one harp in each of the following keys: A, C, and G