Description: Screw top vials are made from first hydrolytic, Type-1, N51A expansion, borosilicate glass. Retrieving Pack Headspace Screw Top Vials, CrossLab, Aijiren Technologies Catalog Number: (AG8010-0417) Supplier: Aijiren TECHNOLOGIES, INC (CSD) Description: These headspace screw top vials have a bevelled top for maximum secure seal.