Quality Environmental Containers. vials come assembled with polypropylene caps with low-bleed 0.125" PTFE/silicone septa inserted (.135" septa for E-series vials). Sizes are 20mL, 40mL, and 60mL. Preparation Levels for products on this page: LEVEL 1: Assembled & QA checked LEVEL 2: Pre-cleaned to EPA . Related Products: 40ml Amber Glass