When installing, the gaps must be strictly maintained, otherwise, for example, the door will knock or noise will occur from the oncoming air flow. The clearance must in any case be parallel, that is, the size of the gap along the entire length of the mating body parts must be the same. The permissible deviation from parallelism is up to 1 mm.
The surfaces of adjacent surfaces must be necessarily parallel. In this case, the displacement of the body element located at the rear is allowed by a maximum of 1 mm inward.
Example: The front edge of the rear door may be a maximum of 1 mm deeper than the rear edge of the front door.