Volumetric Flask, 250mL. These volumetric flasks are highly-transparent, easy-to-clean, and meet Class A tolerances per DIN EN ISO 1042.Flasks are manufactured from virgin PFA , which is highly resistant to heat and chemical contamination. PFA surface properties offer superior cleanability to glass, PTFE and polypropylene containers, reducing risk of sample carryover in trace analysis applications. These beakers are suitable for sterilization using heat, gas, and chemical methods for sensitive biological applications. Screw cap design provides reduced contamination risk, compared to traditional stopper design.