Iso9001 gc vials with screw caps Shimadzu. Screw thread vials & closures for HPLC, GC, MS appliions. There’s a Thermo Scientific screw top vial for every HPLC, GC, MS instrument, appliion, and budget. Our screw top clear and aer glass vials and plastic screw top vials are available in 8mm, 9mm, 10mm, and 13mm screw threads.