Hexagonal Hollow Stopper with Flat End, 19/26, Borosilicate Glass

This hollow glass stopper features a hexagonal top and a flat end, with a 19/26 cone size. Manufactured from heavy-duty borosilicate 3.3 glass, the stopper provides a secure, ground-glass seal for flasks and bottles with matching 19/26 socket joints. The hollow construction reduces weight compared to solid stoppers while maintaining a reliable seal. The hexagonal top provides a secure grip for insertion and removal. Suitable for use in distillation, storage, and general laboratory glassware applications.