The DURAN® premium GL 45 laboratory bottles are moulded from high-purity, clear, USP/EP Type I borosilicate glass 3.3, renowned for its excellent thermal performance, and high resistance to chemical attack. The premium bottles are ideal for high temperature applications: the thermal shock resistance of the glass bottle is certified for a 160 °C differential, and is combined with a high temperature fluoropolymer (PFA) screw cap and pouring ring that are suitable for use up to 200 °C. A combination of high-performance materials and robust ISO 4796-1 design provides a long working life. The bottles feature a double graduated scale for filling volume and a reversed scale for pouring. The marking field and Retrace Code for manufacturing lot traceability are printed in permanent white enamel.