[Regarding] metal utensils, their flatwares and their hollowares are tamei. [If] they break, they become tahor. [If] one refashioned them into utensils, they revert to their former state of tumah. Rabban Shimon ben Gamliel says: [This does] not [apply] to every [kind of] tumah, but [only] to corpse-tumah.

Every metal utensil that has a name of its own is tamei, except for a door, a door bolt, a lock, the socket that is under the pivot, the pivot, the beam, and a pipe, since these are made [to be attached] to the ground.