Those are called rivets which are extremely durable and strong when installed correctly using a rivet gun, however, standard stainless bolts and nuts sourced from a local hardware store will work just as well.
Received my order today Fri Mar 5, as usual excellent service with an excellent product,liked the idea that you guys sold the grill as a 2 piece rather than having to order two seperate pieces,like some of the other suppliers, will be dealing with you again in the future.Cheers Bill
Bill Frizzle
The go to place for mini accessories. They have everything and its all shipped from in the USA. My favorite site I am o it daily and people always ask where do I find this stuff. Outmotoring.com of course!
Tom Dahmer
I have now one of the best Mini Cooper JCW in Switzerland, thank you Outmotoring:)