Filter contains a dual indicator dot, which changes from blue to brown in steam, and to orange in EtO.. Filter guarantees the internal environment of SterilContainer remains sterile until it is opened for use, protecting the integrity of the sterilized instruments.. Filter material is designed to allow the sterilant to penetrate and sterilize the contents within the container: It ensures the sterilization process is efficient by facilitating the even distribution of sterilizing agent.. Post-sterilization, the filter continues to protect the sterilized contents from environmental contaminants until the container is opened..