Strings feature W-Core, a new core material developed by Warchal with the aim of achieving the sound quality of the best gut strings without any tuning instabilities. Distinctive high quality "silking design". Rich and warm sound, rich sound texture. E string is resonant and at the same time gives a silky sound which blends perfectly with synthetic or gut strings. The spiral solution increases the longitudinal elasticity of the string (more similar to gut or synthetic strings).