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 DURAN® 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 45 laboratory bottles are available complete with high temperature screw caps and pouring rings. The red polybutylene terephthalate (PBT) GL 45 threaded caps with PTFE faced silicone cap liner and ETFE pouring rings offer greater thermal and chemical resistance than the equivalent polypropylene components. All components are fully autoclavable at 121 or 134 °C and suitable for dry heat sterilization up to 180 °C. All components are fully compliant with current international food contact regulations such as (EU) No 10/2011.