Hannabach 888MT Greenline String Set for Classical Guitar, Medium Tension, Guaranted nickel and cadmium free.Guaranted nickel and cadmium free.This newly devoped series is based on ecological principles. Many ecological and environment friendly materials are used in the manufacturing process.The basses are made of a newly developed copper magnesium alloy which is free from nickel, cadmium and other bad substances. They are hand machine wound under strict quality supervision. For the protection of the bridge and to guarantee a tight fitting string knot for quick and consistent tuning we use green natural coloured finest biological cotton.We use only one package for the entire set. The package is made from recycled paper and printed with natural inks.For standard scale length 65cm.Trebles:E1 – G3PR („precision round“) professional quality.Coloured markings to ensure easy recognition Basses:D4 – E6 Newly developed copper magnesium alloy wire Free from: Nickel, Cadmium, Lead, Chrome, Cobalt, Potassium, Mercury (tested by an independent scientific institute)Green natural coloured biological cotton on string end.