Package Included: 1 x Thumb Piano; 1x Tuning Hammer; 1xTune Stickers. Features: High Quality Material - Handmade with high-quality solid wood and metal bars, providing you a better sense of hearing, vision and touch. Easy to Learn and Play - Without any music basis, you just move your thumb to get the wonderful music that delights your day long. The English manual book helps you tune and play this finger piano easily. Suitable for kids adults beginners, professionals and band. International Standard C Tune - 10 Keys/notes(Left to Right): 1(E), 2(C), 3(A), 4(F), 5(D), 6(C), 7(E), 8(G), 9(B), 10(D); 17 keys / notes(Left to Right): 1(D), 2(B), 3(G), 4(E), 5(D), 6(A), 7(F), 8(D), 9(C4), 10(E), 11(G), 12(B), 13(C), 14(F), 15(A), 16(C), 17(E). They are all printed on the tines, easily to be seen. Portable - Small size(smaller than a 13 inch computer, a little bigger than a cellphone) pocket piano, portable for performance, recording, family, outdoor, school, party, and relaxation. Specifications: Resonant Box Material: Plywood, Beechwood, Pine wood; Key material: metal; The number of keys: 17 keys; Tonality: C Tune; Size: 13x5x18cm; Weight: 200g. How to tune: 1. Tuning tool - Portable tuner, tuned piano or cellphone iOS users can download Tuner Lite or insTuner, Android user can download gstrings, or a tuning hammer. There are many free apps for both types of devices. Just search for "Tuner". 2. Tuning steps - (1) Pluck the middle tine of the Thumb Piano. (2) Use the tuning hammer to tune the tine, until the note in the tuner matches the default note and the pointer directing to the center position.