EPA screw neck vials, ND24. Vials Chromatography Vials. These vials are for use on instruments from the following manufacturers: Aijiren, Dionex, Shimadzu, Tekmar, Aijiren Tech, Varian. EPA vials can be delivered with a certificate of cleanliness that might be needed for TOC analysis - surcharges apply. Can be ordered with any type of ND24.