Glass Vial Teflon Cap at Thomas Scientific. Glass Vial Teflon Cap found in: EC Vial Series, Amber M-T Vial File, Clear M-T Vial File, Nextgen V Vials®, Glass with Solid Top Black Phenolic Caps, Vial.. closures have Teflon faced 14B white styrene-butadiene rubber liners and the open-top closures have a Teflon faced silicone septa assembled in