Kelim, Chapter Twenty-Eight, Mishnah Eight
1) Poor men’s clothes, though made up of pieces none of which is three [fingerbreadths] square are susceptible to midras uncleanness.
2) If a cloak began to be torn, as soon as its greater part is torn [the pieces] are not regarded as connected.
3) Exceptionally thick or thin materials are not governed by the prescribed minimum of three [fingerbreadths] square.
Section one: Poor people’s clothing is susceptible to midras uncleanness even if each piece is smaller than three fingerbreadths square. This is because poor people settle for whatever clothing they can find and therefore what they consider worthy of wearing might be thrown out by others.
Section two: The two parts of the cloak are considered to be separate once the greater part of the cloak is torn. At this point, if one piece is impure, the other can remain pure.
Section three: If material is exceptionally thin or thick, it is not usable. Therefore, it is not subject to the usual rule that a piece of cloth three fingerbreadths square is susceptible to impurity.