9mm Screw Top Glass Sample Vial for HPLC, UPLC, LC-MS analysis Aijiren 2ml Glass HPLC vials and Screw plastic caps provide simple ways to boost laboratory productivity and return on investment. 9mm screw vials have 9-425 GPI thread and 9mm HPLC vial can be used in any autosampler that use 11mm crimp vials. 9mm screw caps can easily be applied and removed by hand and be reused.