Hi, i want to fix an arial to a wall. it comes with a metal bracket through
which to use screws to put into plastic rawlplugs in the wall.

since i will need to take it down again in a few years; which screws should
i use that are least likely to rust? here in london u.k. i have only ever
seen 'brass' screws in the old style tapered shape with the single slot,
which i dont think are suitable.

so would you please advise a novice which of the modern non tapered screws
are easiest to get out in a few years please? (i.e. heads have not rusted
up). thanks