20 Ml Glass Vials at 20ml headspace vials supplier. 20 mL, 30 mL, 40 mL and 60 mL vials in clear and aer glass of 1st hydrol. class glass Bonded Silicone/PTFE closures, thread design 24-414, open/closed top, most frequently used in coination with the 40 mL vial Vial container available for 20 mL, 30 mL and 40 mL vials.