Double silver medium tension classical guitar strings, ideal for improving sound quality. Strings 1, 2, and 3 are fluorocarbon CX carbon, and strings 4, 5, and 6 are double silver, a medium tension set. Carbon Active Set Medium. - Brand: KNOBLOCH - Model: 300ADC - Type: Classical Guitar Strings - Tension: Medium Tension - Material: Double Silver - Set Quantity: 1 set - String Length: 33.5 - String Length: 31.5 Thank you for viewing.