Sep 27, 2020 · 2ml snap top HPLC vial is made of Type 1 borosilicate glass. Comparing with 9mm screw vial, this 2ml snap hplc Vials mouth is wider opening. So 2ml snap top HPLC vial is easier to fill and provides a larger target area for the autosampler needle. That is to say, the 2ml snap top HPLC vial can protect the needle.