Shimadzu designed the Prominence HPLC vials with superior glass and septa quality, which are critical to enhance performance in HPLC testing. The 1.5 mL and 4 mL sample vials use a PTFE/silicone septum, so their cleanliness is suitable for everyday applications and the most discriminating LCMS analyses. The septum is press-fit inside the vial cap without bonding agents, which eliminates possible sample contamination. The design also prevents an autosamplers needle from pushing the septum into the vial. For high-throughput labs, a snap-cap version of the 1.5 mL vial, using the same PTFE/silicone septum, is also available. A 6 mm opening in the 1.5 mL vials provides a better target for an autosamplers needle and makes filling easier and cleaner. Uniformity of glass vial bottom thickness ensures consistent needle depth from run to run.