If your camped out, and the flies are insane, flystrike powder works great!
Its usually like a white talc. You put it on maggoted sheeps bums and their fleece when blown, or after dehorning etc.
A lure is required, carp or road kill works.
Put it just out of wiff from camp sites, shake some on it.
One second of touching it and they are on their backs in 30 second.
If your away from others...
Just don't backfill your hole
oop: .
Burn ya dunny paper, whizz on it to be safe.
Shake it over it.
You don't end a lot.
About $35 delivered.
500grams.
I put some on a dead yabby head on a plastic meat tray when out in the boat, 500 flies that constantly follow you , and repellents don't kill Them.
At least this way as well, they are history shortly after finding you.