What littlesmoke showed is correct. SEAD is the mission type but ANTI_RADAR is an equally working statement for a SEAD sub-type that's available in the game. When the game generates a SEAD mission, your tasking might be to destroy radars; in that case, you can specify a precise loadout for that tasking, the game automatically chooses the ANTI_RADAR loadout.
We already knew this, we featured it extensively in the ODS 30AE mod, and it's already used on fantastic aircraft add-ons such as the Mirage F1s.