Wheel Center Caps Keep Falling Off

I have a set of STI HD3 wheels and keep losing the center caps. They are only 5 bucks to replace, but I lose one on about every ride. Is there a more durable solution? These are super cheap plastic and break easily. Anytime you drop into a large rut there’s a good chance you broke/lost a center cap. They also stick out kind of far. I would prefer just about anything that stays in place and does not stick out so far.