This is the Pirastro Passione Solo 4/4 Violin E String - Steel - Medium Gauge - Ball End. The Passione Solo A, D and G are gut strings with increased stability. The sheep gut core of the Passione Solo strings are manufactured, wound, and polished in the traditional way: by hand. Passione Solo strings possess a fascinating diversity of sounds, which allows musicians to alter their tone as desired. The core sound is full, round and warm and has a complex overtone spectrum causing a soloistic tone with strong power and brilliance.