21.A.807 Identification of UKTSO articles

(a) Each holder of an UKTSO authorisation under Subpart O shall permanently and legibly mark each article with the following information:

1.  the name and address of the manufacturer;

2.  the name, type, part number or model designation of the article;

3.  the serial number or the date of manufacture of the article or both; and

4.   the applicable UKTSO number.

(b) By way of derogation from point (a), if the CAA agrees that a part is too small or that it is otherwise impractical to mark a part with any of the information required by point (a), the authorised release document accompanying the part or its container shall include the information that could not be marked on the part.

(c) Each person who manufactures an APU under Subpart G or Subpart F shall identify that APU by means of a fireproof plate that has the information specified in point (a) marked on it by etching, stamping, engraving, or other approved method of fireproof marking. The identification plate shall be secured in such a manner that it is accessible and legible, and will not likely be defaced or removed during normal service, or lost or destroyed in an accident.