This 100ml flat-bottom Florence boiling flask is made of heavy-duty borosilicate glass, featuring a long narrow neck with a beaded rim. Designed for use in labs, it is ideal for handling liquids at varying temperatures, thanks to its thick-walled design and superior chemical durability. The flask can withstand high temperatures and thermal shocks, being autoclavable. Eisco Labs' Borosilicate glass has heat tolerances of -515°C (strain point), 565°C (annealing point), and 820°C (softening point). Stopper not included. Eisco Labs ensures premium quality through strict quality control and top-grade raw materials for durability in demanding environments.