THE 427 PACESETTER ELITE SET CONTAINS CLEAR NYLON TREBLES AND BASSES ARE SILVER-PLATED COPPER WOUND ON A NYLON FILAMENT CORE. THE PROTOTYPE FOR THE FIRST NYLON CLASSIC GUITAR STRINGS, THIS FIFTY YEAR OLD SET DESIGN HAS BEEN THE STANDARD AND MOST VERSATILE STRING CONSTRUCTION SINCE NYLON STRINGS WERE DEVELOPED. THE MODERATELY PRICED 427 SET IS BY FAR THE WORLD'S LARGEST SELLING SET OF CLASSICAL GUITAR STRINGS. BRIGHT TONE TENSION: MEDIUM STRING GAUGES: CLEAR NYLON: .028, .032, .040, SILVER-PLATED WOUND: .028, .033, .041 MADE IN THE USA WITH AMERICAN WIRE PACKAGED USING MAP TECHNOLOGY (MODIFIED ATMOSPHERE PACKAGING) TO PREVENT TARNISHING AND ENSURE FRESHNESS