Boeing has told the Federal Aviation Administration that more than 300 of its 737 jets — including the grounded 737 Max aircraft — may contain faulty parts on the wing, the FAA announced in a statement Sunday.
[W]e have determined that up to 148 parts manufactured by a Boeing sub-tier supplier are affected. ... The affected parts may be susceptible to premature failure or cracks resulting from the improper manufacturing process. "— FAA statement