.* Durability and excellent sound are essential for good strings, and each set of Orphee strings are guaranteed to give you a wonderful sounding experience.* The internal wiring is hexagonal steel carbon core, clear and shiny sound and shrill sound.* The tone is rich and warm with abundant harmonics.* Extremely light and high quality, it has a long service life. Extra Light- (9-42) RX15, Blue Pack. For a super easily playable experience, tailored overall to the songs and a nice clean feel.Light- (10-46) RX17, Green pack. This string set tend to be more durable than the "extra light" string set, while maintaining durability and a pleasant sound.Medium- (11-50) RX19, Gray pack. Popular in blues and rock, they provide substantial sound while still allowing for some degree of string bending. Specifications:Brand: OrpheeModel: Extra Light- (9-42) RX15/Light- (10-46) RX17/Medium- (11-50) RX19Quantity: 1 Set/6 PiecesMaterial: Hexagonal Carbon Steel & Nickel AlloyType: Electric GuitarPacking List:1 Set Guitar Strings