PC, PP closure. Autoclavable, transparent. Use for preparation and storage of culture media and many culturing techniques. Far safer than glass flasks for use in shakers. Closures are linerless, noncontaminating. Flasks and closures are autoclavable, but PC shows some loss of mechanical strength after repeated autoclaving. Before autoclaving, set closure on top of the container without engaging the threads. PC, PP closure. Autoclavable, transparent. Use for preparation and storage of culture media and many culturing techniques. Far safer than glass flasks for use in shakers. Closures are linerless, noncontaminating. Flasks and closures are autoclavable, but PC shows some loss of mechanical strength after repeated autoclaving. Before autoclaving, set closure on top of the container without engaging the threads.