Clear vial designed for volatile organic analysis (VOA) Choose from 20mL or 40mL sizes; Closed-top white polypropylene cap with PTFE-faced silicone liner bonded to the cap for a secure seal; Directly compatible with automation; Closures assembled to vials; Includes: Certified: Certified to meet or exceed EPA performance-based standards for volatile organic analysis; Certificate of Analysis (CofA) included in the case and barcoded with lot number for traceability