20 ml (5 dram) Amber vials, green hole caps w/PTFE and silicone. Amber vials offer protection from harmful light and uv rays for light sensitive products. Made of type i borosilicate glass, providing exceptional resistance to heat shock and chemical leaching. The glass is non-porous and has no catalytic affect. Because the boron oxide particles in the glass are so small, the silicate is held more closely together, resulting in a much stronger glass for your laboratory needs. Attached 24-400 polypropylene hole caps are known for good impact strength, cost effectiveness, and pliability. The PTFE PTFE/silicone septa resists coring and is recommended when multiple injections are required. This .125 in septa has excellent resealing qualities.