KIMBLE® KONTES® Glass Chromatography Column manufactured by DWK Life Science is made from 33 expansion, low extractable borosilicate glass conforming to USP Type I and ASTM E438, Type I, Class A requirements. Each column comes complete with a column barrel, a stopcock adapter with a size 2 PTFE plug, two ethylene propylene (EP) O-Rings, a removable 40-60 micron porosity fritted disc and a pinch clamp.