Alice A107BK-H Classical Guitar Strings Set Black Nylon Strings for Acoustic Guitar-5pcs Stings Fit for the regular size of classical guitar nylon string greatly. Made of high-quality nylon or coated copper alloy. Black Nylon:E-1st .0285'' 0.72mm;B-2nd .0325'' 0.83mm;G-3rd .041'' 1.04mm. Gold-Plated Copper Alloy Wound: D-4th .030'' 0.76mm;A-5th .036'' 0.91mm;E-6th .044'' 1.12mm Package Including: 5 set strings