THE TRADITIONAL BLUES TUNING. The Major Diatonic harmonica is the most commonly used tuning for playing Blues, Rock, Country Folk & Jazz. ORANGE LABEL 14 Keys Labeled in straight harp. FEATURES OF THE LEE OSKAR HARMONICA SYSTEM Hi-Tech Slide-Together Interlocking Boxes For carrying convenience and fast, easy indexing. Each tuning is color-coded. Stainless Steel Cover Plates Engineered for excellent projection and tone. Corrosion free. Plastic Comb Eliminates swelling and shrinkage and projects a louder brighter sound. Wide chambers and narrow dividers for ease of playing. Precision-molded, recessed bed holds reed plates securely and prevents air leakage. Replaceable Reed Plates Top quality brass. Keys included: A, B, Bb, C, D, Db, E, Eb, F, F#, G.