Natural HDPE wide mouth round bottles are ideal for general lab use with solids and powders. These HDPE bottles provide an excellent moisture barrier and are impact resistant. They are ideal for high-speed filling, demanding pharmaceutical specifications and the rough handling of interstate shipping. Attached green thermoset (phenolic) are known for providing the widest range of chemical compatibility and for being the most temperature tolerant of plastic closures. The color green easily identifies the PTFE liner system. foam backed PTFE liners resist attack from virtually all chemicals at room temperature and provides resilience for a tight seal with a low moisture transmission rate. F217 has a low density foam core between two solid layers of ldpe. uses include analytical lab samples, high purity chemicals, strong acids solvents, environmental samples, pharmaceuticals, and diagnostic reagents.