The evacuation and replacement method of MacIntosh & Fildes is said to be the most efficient way to create anaerobic or micro-aerophilic conditions, eliminating the disadvantages of conventional methods. The method is used in conjunction with anaerobic jars to achieve maximum flexibility.
Mart Microbiology B.V. has perfected this method in the Anoxomat system.

The Anoxomat evacuates a portion of the jar contents, and refills the jar with an anaerobic gas mixture, usually consisting of Nitrogen 80%, CO₂ 10% and Hydrogen 10%. During this procedure the Oxygen concentration in the air is rarefied.

More information can be found under User defined atmospheres.