Keilim, Chapter 17, Mishnah 3. This chapter is occupied with measurements, and in particular with the size of hole that puts an end to a vessel's usefulness. Once a container can no longer do the job for which it was made, it is no longer a kli at all, and a vessel that is not a kli cannot receive tumah. Our mishnah continues that theme with additional kinds of containers that have developed holes, and it adds a further question: when a broken basket has been patched up, is the repair good enough to restore it to the status of a vessel?
The first case is the bread basket. The mishnah says "hasalim shel pat", baskets in which loaves are kept, and their measure, "shiuran", is fixed "bekikarot shel pat", by whole loaves of bread. Whatever a container was built to carry is what determines how large a breach has to be before it counts. While the loaves stay inside, the basket is doing its work and remains a kli. Once the gap widens enough that a loaf slips out through it, the basket can no longer serve the purpose for which it was made; it has forfeited the title of utensil, and it is therefore tahor.
Next comes the "apifirot", a hamper woven from a mesh of reeds, whose floor gave way. Its owner tried to salvage it: "asa la kanim", he set reeds into it, "milemata lemala", running them from beneath upward, "lechizuk", so that they would brace the collapsed base. The verdict is "tehorah". At this moment the reeds really are holding the bottom up, but the arrangement will not last. Load the hamper with produce and the weight will press on those reeds until they shift and slide out of position. An object that cannot retain the very contents it was fashioned to carry is not a kli that tumah can take hold of, and so from here on it is tehorah.
Now a better repair is described: "asa la gapin kolshehen", he fashioned hooks for it, however small they may be, and the ruling becomes "temei'ah". What exactly did he do? He bent the upper ends of the bracing reeds around the hamper's border and locked them there, so that they can no longer work themselves loose. With the reeds anchored at the edge, the floor stays supported even when the hamper is full. It performs precisely the function it always performed. Since the break has been genuinely mended, the hamper reverts to being a utensil capable of contracting tumah.
A dissenting standard closes the mishnah. Rebbi Shimon holds: "im eina yechola", if the hamper is unable "lehinatel bagapayim", to be lifted by its hooks, then "tehorah". He offers a practical test. Grasp nothing but the hooks and raise the hamper. If the bracing reeds tear away under the strain, those hooks never produced a repair that endures. The fracture in the floor is still a fracture, the object remains a broken basket, and it does not receive tumah.
The thread running through all three cases is the same principle. Tumah attaches to a vessel that functions, and functioning is judged by the ordinary use for which the vessel was made: bread that stays in the basket, and a bottom that holds its contents rather than a patch that gives way under weight.