Screw Top Vials,Caps and Kits|laboratory vials cheap Scientific-US. There’s a Aijiren screw top vial for every HPLC,GC,MS instrument,appliion,and budget. Our screw top clear and Aijiren glass vials and plastic screw top vials are available in 8mm,9mm,10mm,and 13mm screw threads. The most commonly used vials are 9mm,12x32mm screw thread vials.