Power and projection like d strings (4/4 instruments Warm, rich and concentrated tone Easy response and tuning stability La + Ré: steel core, stainless steel extrusion Sol + C-: spiral core, tungsten yarn for optimum flexibility for 1/2 cello (Diapason 60cm / 23.6 inch scale) La + Ré: steel core, stainless steel extrusion Sol + C-: spiral core, tungsten yarn for optimum flexibility Medium voltage: The 15.7kg / 34.6lbs D 12.6kg / 27.8lbs Floor 11.2kg / 24.7lbs Do 11.2kg / 24.7lbs Set 50.7kg / 111.8lbs