The Teflon filter element is sintered from pure Teflon particles and does not use any other substance in the structure. These filters are usually provided when only 100% pure PTFE can be used. If appropriate, it is usually best to provide K-type secondary filter element, because the pressure drop and life characteristics are better than PTFE filter element. The advantages of PTFE are higher temperatures, up to 200°C, and better chemical resistance. These elements shall be cleaned by ultrasonic wave to obtain the best results.