McIntosh and Fildes’s anaerobic jar is a tool utilized in microbiology laboratories, to generate anaerobic circumstances (anaerobiosis) to cultivate obligate anaerobes, such as Clostridium spp. Anaerobiosis derived from McIntosh and Fildes anaerobic jar is among the most effective and most frequently employed methods for anaerobiosis however it requires expensive special equipment and a vacuum pump. Gas supply availability is another drawback to this technique. It is currently being replaced with an easier GasPak system.