DURAN® Original Laboratory Bottle, clear DURAN® Original GL laboratory bottles have become the gold standard of multifunctional laboratory bottles since their introduction in 1972. The 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. A combination of high-performance materials and robust ISO 4796-1 design provides a long working life. The bottles feature an easy-to-read graduated volume scale, and marking field in permanent white enamel. Permanent Retrace Code on each bottle for manufacturing lot traceability. DURAN® Original GL bottles are supplied complete with iconic blue polypropylene cap and drip-free pouring ring for use up to 140 °C. All components are fully autoclavable at 121 or 134 °C.