This record has the same format and meaning as record 0, see there for more information. It is used to report minefields with Id numbers above 500.

When AllowMoreThan500Minefields is turned off for a player but there is a minefield with an Id number above 500, PHost will send this record type. When AllowMoreThan500Minefields is turned on, all minefields will be reported using record type 0.