FAA unapproved parts notifications

When the FAA finds parts produced or sold for certificated aircraft without approval, it publishes an Unapproved Parts Notification naming the producer and the parts. This is the full list, searchable. Every part number and every vendor on PartsAndPlanes is checked against it automatically; a match shows on the part page and the vendor page. Read the notice itself before acting on a match: a part number can be legitimate from an approved source and unapproved from another. See also condition codes and the paperwork to expect.