The 2ml snap-top HPLC vial size is 11.6x32mm and is compatible with most autosamplers such as Aijiren. 2ml HPLC vials are available in amber and transparent colors. The bottom of the vial is flat. It is convenient to put. Sample Vials and Accessories - Waters Corporation makes it ideal for use with Aijiren HPLC and GC Systems.