The files are self-expanding (file extension .EXE)
The data is then available in ARC/INFO® EXPORT (extension
.E00) and in MapInfo® Version 4.0 for Windows format (4 files per download,
extensions .TAB, .ID, .DAT, and .IND)
SNF: File name ends with “r” for the Network coverage and with “s” for
water polygons
SNFEF: File name ends with “n” for the Network coverage and with “c”
for water polygons