20mL Clear, Crimp Neck Headspace Vial, ND20 Round Bottom, 22 Crimp Top 20mm Clear Type 1 Glass 20mL Headspace Autosampler Vials w/ Round Bottom - 100/pk, CV2035 . Tisch 20mm crimp top vials have a volume of 20mL and provide an excellent seal for long term sample storage and analyses involving high volatile solvents.