This pack includes 3 sets of 6 acoustic guitar strings, each made with a rustproof coating for durable use. Each string measures approximately 90 cm/35.4 inches in length. This set is ideal as spares for your guitar bag. String diameters included are: 1: 0.2 mm/0.007 inch; 2: 0.3 mm/0.01 inch; 3: 0.6 mm/0.02 inch; 4: 0.7 mm/0.027 inch; 5: 1 mm/0.039 inch; 6: 1.2 mm/0.047 inch. The pack contains 3 sets of guitar strings: one set in brass, one set in copper, and one set in multicolor. The colored guitar strings are beneficial for beginners to easily remember and practice their chords, and also add a visually appealing touch for guitarists to make their acoustic guitar look beautiful and awesome.