D'Addario Zyex Viola Single C String, Long Scale, Heavy Tension Long-scale viola (body length 16-16 1/2 inches) with a playing length of 15 inches (380mm) Heavy tension Zyex synthetic core produces a rich, warm tone Short break-in time and excellent bow response provides superb playability and a broad tonal palette All D'Addario strings are designed, engineered and manufactured in the USA to the most stringent quality controls in the industry