Aijiren headspace vials are offered as 10 mL vial and 20 mL certified screw vials and certified crimp vials, clear glass or amber glass headspace vials and associated 11 mm crimp caps , 18 mm screw caps, 20 mm crimp caps and 22 mm crimp caps while being are engineered to prevent sample contamination providing a consistent, secure seal of the . These headspace vials come in both flat- and round-bottom styles for use in a wide variety of headspace instrument platforms.