Narrative:

Captain's oxygen mask microphone inoperative wrong mask part number installed. Mask was replaced next stop. Aircraft flew from msp to ord with wrong part installed. The installed mask was serviceable and microphone did work.

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Original NASA ASRS Text

Title: A B737-200 WAS DISPATCHED WITH THE CAPT'S OXYGEN MASK MIKE INOP DUE TO WRONG TYPE MASK INSTALLED.

Narrative: CAPT'S OXYGEN MASK MIKE INOP WRONG MASK PART NUMBER INSTALLED. MASK WAS REPLACED NEXT STOP. ACFT FLEW FROM MSP TO ORD WITH WRONG PART INSTALLED. THE INSTALLED MASK WAS SERVICEABLE AND MIKE DID WORK.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.