/sys$common/syshlp/helplib.hlb NCS Command, Command Qualifiers, /OUTPUT  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  /OUTPUT[=output-file-spec]

   This qualifier may be used with either  the  /EXTRACT  qualifier  or
   with the /COMPRESS qualifier to specify the output destination.

   Use /OUTPUT with the /EXTRACT qualifier to  specify  a  destination
   file for the source definitions extracted from an NCS  library.  If
   you omit the file type when you use the /OUTPUT qualifier with  the
   /EXTRACT  qualifier,   NCS  assigns  the  destination  file  a  NCS
   extension. Note that the new source file is not  the  same  as  the
   source file used to originally  create  the  definition.   The  NCS
   utility does not store the original source file, only the resultant
   definition.

   Use /OUTPUT with  /COMPRESS  qualifier  to  specify  a  destination
   library file for the compressed library.  If you  do  not  use  the
   /OUTPUT qualifier  with  the  /COMPRESS  qualifier,  NCS  puts  the
   compressed library in a new version of the default NCS library.  If
   you omit the file type when you use the /OUTPUT qualifier with  the
   /COMPRESS  qualifier,  NCS  assigns  the  destination  file  a  NLB
   extension.