These PYREXPLUS® volumetric flasks feature a protective PVC coating for longer product life and safety. Protective coating helps prevent glass from shattering and reduces spills. Flasks are autoclavable (121°C) and resistant to thermal shock. The strength of these flasks has been increased appreciably through machine-blown bodies to which are sealed heavy-tubing necks tooled for Standard Taper glass stoppers. The graduation line is sharp and permanent and large white block letters make the inscription easy to read.