2ml Autosampler Vials 8-425 neck finish represents a hplc vials &gc vials, the vials a diameter of 8 mm across the outside of the threads and a thread style of 425, Vials has clear and amber, Screw Cap in Lab most of the 2ml vials are 12*32mm. The design of Aijiren screw thread top vials is developed from Europe and the United States, and the design feature is easy to use, especially the use of an automated sample introduction system.