This is the category people skip, and it is the one that causes noise and uneven wear. A caliper that slides on dry, corroded pins will drag one pad and leave the other doing nothing. A missing abutment clip lets the pad rattle in the bracket.
Kits are listed as front or rear and as one axle or one wheel. Read the listing, because one axle kit on a vehicle with four-wheel discs is not enough for the whole car.
Bolts that are specified as torque-to-yield should never be reused. Where a listing supplies a new bolt, that is deliberate and not padding.
