are those made out of metal or ?
I honestly don't know - I found them by googling 'small round motorcycle LED indicators'... and this website popped up:
http://www.norbsa02.freeuk.com/goffyleds.htmMaterials aren't mentioned in the product description.
I figure they would only just peek out either side of the license plate if a tail chop kit was used... so they would should be nicely out of the way.