12x32mm testing HPLC sample vials natural rubber-Aijiren HPLC 22/03/2020 · Note: Most 12x32 mm autosampler vials hold between 1.5mL to 2mL of solutions. The sizes for 12x32mm vials outer dimensions are standard between manufacturers but the length of the neck and screw thread of the 9mm (N9) vial may vary, because 9mm short thread is not industry standardized..