May 30, 2018 · ND8mm Screw Thread Autosampler Vials are made of clear Type 1, Class A Borosilicate Glass with a writable label for sample identification. 2. Sample Vials with unique thread design ensures consistent seal and can be reused, not volatile, easy to use ; 3. Screw Neck Vials ND8, small opening, 8-425 thread 2ml Capacity ,12x32 mm Dimensions ; 4.