Headspace vial kit with 20mL (75.5 x 22.5mm) crimp neck, clear glass, round-bottom vials and red magnetic caps with PTFE/silicone septa. Recommended for the HS-10, HS-20, AOC-5000 and AOC-6000. For 20mL round-bottom vials with magnetic screw caps, use 220-97331-16.