Scaled to fit 4/4 size cello with a playing length of 27 1/2 inches (700mm), medium tension strings are optimized to the needs of a majority of players. This A string is aluminum wound. Pro-Arte synthetic core cello strings have a warm, mellow tone. They are less sensitive to humidity and temperature changes, and break in quickly. Pro-Arte strings are manufactured at a lower tension in order to maximize bow response, tonal blend and playability. The perfect choice for players seeking a warm, dark tone.