Made of colorful coated copper alloyLong service lifeTunes stable, sounds greatSuitable for acoustic guitarLength: approx.1 m (40inch)6 different colorful strings:E string (1st) .011inch(0.28mm) stainless steelB string (2nd) .015inch(0.38mm) stainless steelG string (3rd) .024inch(0.61mm) red bronze woundD string (4th) .032inch(0.81mm) yellow bronze woundA string (5th) .042inch(1.07mm) blue bronze woundE string (6th) .052inch(1.32mm) green bronze woundMaterial: Copper alloyPackage Includes:12 x Guitar strings.Only the above package content, other products are not included.Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.