Filter Vials & Accessories. Thomson SINGLE StEP* Filter Vials are simple replacements for HPLC Vials, HPLC Caps, Syringes, Needles, and Syringe Filters. Filter Vials are simple protection for HPLC, GC, GC/MS and LC/MS systems. They minimize steps and loss of product. They are universal for all different types of autosamplers including UHPLC.