במה דברים אמורים, בשהיה הכלי הגדול שיש בתוכו הכלים הטמאים טהור, אבל אם היה טמא, מתוך שעלתה לו טבילה, עלתהא לכלים שבתוכו אפילו להשתמש בהן בקודש:
A person may immerse keilim inside other keilim to use for terumah, but not those to be used for consecrated foods. This is a decree lest the opening of the container be narrow and not be as wide as the mouthpiece of a drinking pouch. Thus the keilim inside of it would be considered as if they were immersed in the waters of the k'li and not in the waters of the mikveh. When does the above apply? When the large container in which the small impure keilim were placed was pure. If, however, it was impure, since the immersion is valid for it, it is also valid for the keilim inside of it, even though they were to be used for consecrated foods.