There is a duty free shop right near the bridge connecting Jordan and Israel. You can just go in, in the sort of no-man's land and buy stuff duty free in middle of the desert.
All duty free shops are the same. There are cigarettes, liquer, and junk that you really don't need. You can never find anything useful in them. I spend much time browsing duty free shops, never finding anything interesting or anything different from any other duty free shop.