Set with synthetic core and E-string plain steel with ball end, with strings E I, A II, D III, G IV. The ball ends are removable. D-string is silver wound. The sound of the Thomastik Vision strings is focused, clear, open and brilliant. They can be mixed and matched with almost any synthetic core string. Thomastik no. Vi100 3/4 (incl. Vi01, Vi02, Vi03, Vi04).