Straps for insulated PEX

[ASZFromSeattle]

I'm adding some new PEX A pipes to my house, and I've insulated them with foam insulation prior to securing them so the insulation is continuous. Am I allowed to use metal straps like this one on top of the foam to secure it to joists in my crawlspace? Or would I need to use plastic ones? This my first time running supply lines. Any advice would be greatly appreciated.

Thank you.