Best is to check the cans to make sure it’s for metal. But five or six years ago, I painted our outdoor metal table and chairs with rustoleum, black matte/flat. All of it remains outside here around because we live in Southern California. It wasn’t until last fall that I noticed even a small chip anywhere on the table, and none on the chairs. I spent most of my time doing the prep work, cleaning, sanding, and wiping down. If I remember correctly, it was a can that combined primer and paint.

I do use a separate primer when I paint metal. Its also rustoleum spray primer. Make sure it says on the can that it is for metal, for both paint and primer. I have a turquoise on my metal table and chairs and its been on there for about 5 or 6 yrs. Some of the chairs, could use a touch up this year, but, its held up great, to a lot of use.

Definitely go with a matte finish, not gloss.