Clear borosilicate glass vial designed for water sample collection for volatile organic analysis (VOA) Vial shoulder slope optimized to prevent air bubble entrapment; 40mL size; Open-top white polypropylene cap; Septum is low in free-siloxanes: Ideal for in-vial heated purge and trap methods like EPA Method 5035 where siloxane peaks may interfere with target analyte detection; Septum is not bonded to the cap and may be replaced as needed