15 x 45mm 1 dram (4ml) Clear Borosilicate Vial with 13-425 Green Thermoset F217 & PTFE Lined Cap attached, Cleaned for Volatiles. Clear VOA Vials or borosilicate glass vials KaptClean® for Volatiles are designed for EPA volatile organic analysis (VOA.) Volatiles are chemicals that have high vapor pressures at room temperature (easily evaporate.)