Apart from the plain mandolin E string, these Thomastik-Infeld 154W Mandolin strings are made of finely polished tin-plated silver steel, flat wound with chrome steel wire. Their elastic, steel alloy core has excellent sustain. On the instrument, the mandolin strings sound clear and brilliant, with no metallic twang. The string's structure has been optimized for tremolo play. This string set responds well to fast changes of fingering. Tuning is stable and the strings are durable. Thomastik-Infeld mandolin strings are supplied in pairs, and we recommend changing strings two at a time.