Hohner Pro Harp Harmonica, Key of C Hohner's diatonic harmonicas set the industry standard through their high quality construction, excellent response and unsurpassed tone. Often called "Blues Harps" Richter tuning and undivided air channels allow for bending and overblowing the reeds, creating the signature wailing sound typical of the harmonica. The Pro Harp has the same sleek black non-stick covers as the Cross Harp, with a polished plastic comb and standard thickness reedplates.