Strings are New Nylgut, Key of C (GgCcEEAA, bass to treble), the low G string is a Red Series string. Made in Italy, New Nylgut is a formulation of polymerized plastic mixed with additives and patented by Aquila. It has the closest sound to gut strings we have heard. Red Series strings are a mix of New Nylgut and red copper powder, resulting in a string with about twice the density.