PTFE-Faced Butyl Septa for 40 mL VOA Vials, 41 mm, 100/Pack

PTFE-Faced Butyl Septa for 40 mL VOA Vials, 41 mm

ZHC LAB’s PTFE-Faced Butyl Septa are designed as direct-fit replacements for septa used in 40 mL VOA and TOC sample vials with standard 24-400 open-top screw caps. Each septum features a dual-layer PTFE face bonded to both sides of a butyl rubber core, combining the chemical inertness and ultra-low extractables of PTFE with the elastic re-sealability of butyl rubber. The PTFE faces eliminate direct contact between the sample or headspace and the rubber substrate, minimizing analyte adsorption and background contamination critical to trace-level VOA analysis. The butyl rubber core provides consistent elastic recovery for dependable re-sealing after repeated needle punctures. Available in 10/Pack for trial and bench use, or 100/Pack for high-throughput and field sampling workflows.

DIMENSIONAL SPECIFICATIONS:
Diameter: 41 mm
Thickness: 3 mm
Construction: dual PTFE-faced butyl rubber (PTFE face on both sides)
Compatible cap size: 24-400 open-top polypropylene screw cap for 40 mL VOA/TOC vials
Temperature range: -10deg C to +120deg C
Pack sizes: 10/Pack or 100/Pack

COMMON APPLICATIONS: Replacement septa for 40 mL VOA environmental water sampling vials; TOC and DOC sample container resealing; volatile organic compound preservation during sample transport and storage; field and laboratory use in EPA Methods 524, 5030, 8260, and related VOA protocols; general sealing of 40 mL sample vials in environmental testing, industrial hygiene, and analytical chemistry workflows.

USAGE NOTES: Insert septum into open-top cap with PTFE face oriented toward the sample interior. Tighten cap firmly to achieve a leak-tight seal. Designed for use with standard hypodermic needles (18-23 gauge); avoid oversized needles that may cause coring or fragmentation. For VOA applications, fill vials without headspace and ensure no air bubbles form beneath the septum. Single-use recommended for EPA-method critical applications; re-use acceptable for lower-sensitivity workflows. Store in original packaging away from UV light, ozone, and organic solvent vapors.