File: Model-01a.bak (backup copy, various)
File: Model-01a.ddb (Probably text)
File: Model-01a.fre (Probably text)
File: bottom.txt (ASCII or Unicode plain text file)
File: doc.txt (ASCII or Unicode plain text file)
File: drill.txt (ASCII or Unicode plain text file)
File: m01a.zip (popular compression format)
File: top.txt (ASCII or Unicode plain text file)