silver-plated copper alloy wound strings.The entire string select high quality raw materials.Abundant pronunciation, automatic winding strings production.Perfect strings for your acoustic guitar. A104 Silver Plated Copper alloy Music Instrument Strings Set Replacement for Acoustic Guitar 0010-0047 InchSize:E-1st: 0010 inch / 025mmB-2nd: 0014 inch / 036mmG-3rd: 0023 inch / 058mmD-4th: 0030 inch / 076mmA-5th: 0039 inch / 099mmE-6th: 0047 inch / 119mmMaterial: Copper alloyColor: SilverTone: Full TonePackage Dimensions: 10*10*1cmPackage Contents:6* Only the above package content, other products are not included.Note: Light 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.