Compared to the standard DURAN® Erlenmeyer flask, the products of the Super Duty range have a significantly increased mechanical sturdiness due to greater uniform wall thickness. The reinforced, sturdy rim is another advantage as it further increases the shock resistance and notably reduces the risk of breakage. Accordingly, this extension of the DURAN® portfolio offers the user optimum safety when these products are used under heavy mechanical strain, for example with frequent cleaning, but also with the general handling in the laboratory. Thanks to their longer useful life resulting from increased shock resistance, the Super Duty glassware is economically more efficient. To avoid thermal stressing of the glass, uniform and slow heating of Super Duty products is recommended. When working at very high temperatures, or if rapid temperature changes are expected, standard DURAN® Erlenmeyer flasks should be used, as these are characterized by excellent thermal shock resistance. However, the mechanical sturdiness of these DURAN® standard products is limited compared with the Super Duty range. Super Duty Erlenmeyer flask with Retrace Code (Batch Certificate of Performance via Internet).