* OMGEANT/MODIFICATION/MAGFIELD MAF FIELD

   MAF        I 'the magnet number'
   FIELD      R 'Field kGs' D=0

     Changes the values of the field (AMAGPAR(5,mag)

 * OMGEANT/MODIFICATION/MAGSIZE MAF X Y Z

   MAF        I 'the magnet number'
   X          R 'Full size in X' D=-999
   Y          R 'Full size in Y' D=-999
   Z          R 'Full size in Z' D=-999

     Changes the dimensions of the magnetic field (PMOLMAG(2-4,mag)
     Negative values are ignored.