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 3/4 cello (Diapason 65cm / 25.6 inch scale) La + Ré: steel core, stainless steel extrusion Sol + C-: spiral core, tungsten yarn for optimum flexibility Medium voltage: The 16.5kg / 36.4lbs D 13.5kg / 29.8lbs Floor 12.8kg / 28.2lbs Do 12.8kg / 28.2lbs Set 55.6kg / 122.6lbs