GC Vials ND20 headspace 20ml (Crimp Vials) 20mm Aluminum Crimp Cap Seals and Vials ensure that a proper seal is made for this demanding application . Vials are manufactured of Clear, Type 1 Class A or Amber, Type 1 Class B borosilicate glass and include. crimp vial for hplc with ptfe liner pp cap Perkin Elmer