10ml Crimp Top 20mm Headspace Vial for SHIMADZU. The 18mm screw thread 10ml gc vial produced by Aijiren has a specification of 22.5*46mm, and the glass is borosilicate glass, all of which are 5.0 type. The round bottom design prevents reagents from remaining on the bottom of the 18mm screw thread 10ml gc vial.