The 2001 Hard Tension strings are designed to meet the needs of contemporary guitarists and luthiers. These high tension strings provide a superior strength and clarity of sound- a requirement for performing modern technique on today's concert guitars.The 2001 Series® Classical Guitar Strings are the product of years of intense research and development. During the formulation of the 2001 Series, prototypes were tested worldwide by fine performing artists and teachers. These guitarists expressed a need for classical guitar strings with a greater response, clarity and sustaining power. To meet this demand, La Bella redesigned both the treble and bass strings according to new specifications.- Nylon 202 trebles produced greater aural transparency and sound projection- Silver-Plated wound basses produce exceptional memory for pitch and consistent sound production- Hard Tension- String Gauges: Clear Nylon Trebles: .030 .0335 .041; Silver-Plated Wound Basses: .029 .0365 .044- Made in the USA with American Wire- Packaged using MAP Technology (Modified Atmosphere Packaging) to prevent tarnishing and ensure freshness