KIMBLE® KONTES® Jacketed Distillation 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. It comes with a Standard Taper outer joint at the upper end and a Standard Taper inner joint with drip tip at the lower end. Inner tube has a single ring of indentations near the exit end to support packing material.