The Major Diatonic Harmonica Is The Most Commonly Used Tuning For Playing Blues; Rock; Country Folk & Jazz. Major Diatonic Harps Are Produced By Several Manufacturers Using Various Names Such As Blues Harp; Marine Band; Golden Melody; Big River; Special 20; Pro Harp; Folk Master; Star Performer; Etc. Although The Cover Plates Are Stamped With A Variety of Different Names For Marketing Purposes; All of These Harmonicas Have The Exact Same Notation Layout As The Lee Oskar Major Diatonic.