Scaled to fit 4/4 size violin with a playing length of 13 inches (328mm), these medium tension strings are optimized to the needs of a majority of players. The E string included with the H310 set is a plain steel E (tin-plated high-carbon steel) with no winding. Packaged in uniquely-designed sealed pouches providing unparalleled protection from the elements that cause corrosion. Helicore violin strings are crafted with a multi-stranded steel core, resulting in optimal playability while producing a clear, warm tone. The smaller string diameter provides quick bow response. Premium quality materials combined with skilled workmanship produces strings known for excellent pitch stability and longevity. 4/4 scale violin with a playing length of 13 inches (328mm) Medium tension Stranded steel core provides optimum playability and produces a clear, warm tone Versatile string that works well for a wide variety of playing styles and instruments All D'Addario strings are designed, engineered and manufactured in the USA to the most stringent quality controls in the industry