D’Addario DZ310A 4/4M violin string set with aluminium medium tension 4/4 violin size and a playing length of 13 inches (328 mm) tuned Medium Tension, aluminium wound D string (also available silver wound) Zyex synthetic cores produce a rich, warm tone Quick adjustment and excellent bow response for premium feel and a wide tonal range All D’Addario strings are designed, engineered and manufactured in the USA according to the industry’s strictest quality controls