The number - BOEING CSTG 65B84045 - is a casting number so it isn't specific to one particular plane, Alan Lery of Turbo Resources International, Inc., an Arizona aircraft parts reseller, told the Post.

'Sometimes the airlines track every single part number that comes with the plane, but not likely this, he said.
Chuck Horning of Embry-Riddle Aviation University in Florida, also told the Post that the number cannot be traced.
'I would think that it will be difficult to determine specifically which aircraft the assembly came from,' Horning said.
'Being that both aircraft [in the World Trade Center attacks] were B767-200, they both likely had components with the same casting number,' he added.