The mark, as illustrated in the accompanying drawing, comprises the product configuration of a set of bass guitar strings. Specifically, the mark comprises the particular color silk wrap used on the end of each string where it is wound around the guitar peg. The lining in the drawing is used to indicate color pursuant to 37 C.F.R. 2.52 (e). Accordingly, the silk wrap of the low-B string (first from the top in the drawing) is purple, the silk wrap of the E string is red, the silk wrap of the A string is blue, the silk wrap of the D string is black and the silk wrap of the G string (lowest string in the drawing) is green.