The champagne flute Bach is a high-tech blown lead-free crystal glass that does not contain any heavy metals. This glass presents outstanding chemical, optical and mechanical properties. Totally transparent: ultra clear crystal glass according to ISO/PAS IWA 8:2009. Resistance of the rim 37.5%. Resistance to impact test 105% High resistance to breakages. Resistance to twisting of stems {drying by hand) 98%. Resistance to washing cycles 4.000. No alteration in transparency and brilliance over 4.000 industrial washing cycles. Sound amplifier. Dishwasher safe.