Material certificate

That the material is what was specified, traceable to a heat or batch

First article report

That one part matches the drawing, dimension by dimension

Inspection record

That a defined sample was measured against a written method

Surface finish record

That the finish was measured rather than judged by eye

Process record

Which operations ran, in which order, on which batch

Revision statement

Which drawing revision the batch was made to

Packing record

How the batch was packed, and what it was packed in

An illustrative list for a fictional range. A real programme agrees which documents are required, in what form, and how long they are retained.

The one that is most often missing.

The revision statement. A certificate that says what the part is made of, without saying which drawing it was made to, cannot settle the question that most often arises.

Retention is part of the specification.

A record that is destroyed after a year is a record that will not exist when the question is asked, and the question is usually asked years later.