Metal Fusion’s Designated Engineering Representative (DER) Repairs In addition to repairs from the OEM manuals, we also have six DER approved repairs that we developed ourselves and are listed here for convenience.  (Denotes DER repair) OEM Part MFI Repair DER? Garrett 331 APU 3rd Stage Labyrinth Seal MF-60-49-24-12-R01 Garrett TSCP 700 LP Compressor Interstage Housing MF-30-49-23-06-R01 Garrett Air Cycle Impeller Assembly P/N 801414 -1/-2...