The XtraDry positive displacement dry pump technology has a simple piston style design that does not expose bearings to high vacuum conditions. It provides a hydrocarbon-free vacuum and does not generate particulates that can contaminate vacuum processes. It has a flexible and simple, low vibration design that permits multiple pump configurations while having few moving parts. Pumping speed is independent of gas species with a two-stage version providing a pumping speed of 7 m3/h and a base pressure of 0.05 mbar. A single-stage model has a pumping speed of 14 m3/hr and a base pressure of 3 mbar.