Mishnayos Keilim Perek 9 Mishnah 2

ומניקת בתוכה (and a syphon/tube is in it) – like a kind of hollow reed made from metal, that they place one head in the perforation of the jar and he sucks/drains with his mouth from the other head, and all of the liquids that are in the jar go out through this syphon/tube.

החבית והמשקין טהורים והמניקת טמאה – the earthenware jar, but the syphon/tube that is within it is of metal. Therefore, the jar and the liquids that have no purification if the Mikveh, but if it purifies them and they belong to a commoner/uneducated person [who is not careful in the observance of laws of ritual purity], a Haver/member of a group dedicated to the punctilious observance of the commandments should not come to use them, for they are separated from their contact and if it is not, it would be so that all of its food is impure, the Rabbis did not make a decree concerning this, and they are protected/saved by an airtight lid, but a metal syphon/tube that has purification in a Mikveh/ritual bath, if one would purify it, a Haver/member of a group dedicated to the punctilious observance of the commandments would come to use it and he would borrow it from a common/uneducated person [who is not careful in the observance of the laws of ritual purity and immerse it [in a Mikveh] and when its sun had set (i.e., a sunset had passed for this object), he would use it, thinking that there is nothing in it other than because of contact with something impure, but he did not know that it had been in the tent of a corpse and it requires sprinkling [of a mixture of the ashes of the red heifer with waters of purification on the third and seventh days to purify it from the impurity imparted by a corpse, but even though it was in an earthenware vessel that is covered with an airtight lid, the airtight lid of vessels of a commoner/uneducated person [who is not careful in the observance of the laws of ritual purity] save/protect it from the defilement with a Haver, for all of the vessels of a commoner/uneducated person are under the presumption of defilement concerning a Haver, and an impure vessel does not protect/save with an airtight lid, for an airtight lid only protects/saves for a pure earthenware vessel alone. But whereas the Sages came to make a decree that the no earthenware vessel belonging to a common/uneducated person [who is not careful in the observance of the laws of ritual purity] does not protect [even] with an airtight lid, the people of the lands would not accept it from them. Because they would hold that they are expert and preserve their vessels/utensils in purity. Therefore regarding earthenware vessels and food and liquids which do not attain purity in a ritual bath/Mikveh, when they were within an airtight lid of a utensil belonging to a common/uneducated person, they say to them that they are pure and they would use them for they hold their vessels/utensils to be under the presumption of ritual purity, they should not be concerned lest the Haver should borrow from them, for they are, concerning him, in the presumption of being ritually impure and they don’t have purity ever, but a vessel that requires only rinsing in order to be restored to Levitical cleanness where there is a concern that perhaps the Haver will borrow it from them and he will immerse them [in a ritual bath] and use them without sprinkling [of a mixture of the ashes of the red heifer with waters of purification] on the third and seventh days [to purify it from the impurity imparted by a corpse], they made the law equivalent for all and stated that a vessel requiring only rinsing in order to be restored to Levitical cleanness is protected/saved by an airtight lid.

ובית הלל אומרים אף מניקת טהורה – prior to their having heard the reasoning of the School of Shammai they did not know for what reason foods and liquids that are within an airtight lid are pure and metal vessels are impure, but after they heard their reasoning as we have explained, they (i.e., the School of Hillel) retracted to teach according to the words of the School of Shammai.