Schott Zwiesel's Convention Glassware and stemware are made of Tritan^® Crystal , a quantum leap in lead-free crystal.

Tritan^® Crystal is made with Titanium and other proprietary ingredients, making it highly dishwasher safe, exceptionally clear, and enduringly brilliant. All Tritan^® Glassware is tempered at the rim for maximum strength and chip resistance; stemware is also tempered at the joints of the neck and stem and the stem and the base for maximum durability.