[Blue Bomber]

Rustoleum spray paint works fine, too. Had it on my calipers for 2 years with no fading or chipping.

 

[Blue Bomber]

The color I used was metallic black, so it's somewhere in between flat and gloss. It's kinda like a textured gloss. Some wet sanding and some clearcoat would bring it to a full gloss. I've also used Rustolem non-metallic colors, and if you do it right, it can be very glossy without clearcoat.