They fit perfectly my '71 Demon disk rotors. Original wheel studs don't stick out of the 1" adapter.
They are made of 6061-T6 aluminium, and are anodized.
As the center hole is big (73mm), the adapters are stud centric. But I don't think that this will be a problem as it's a true 5X4" SBP (not 100mm) to 5X4.5" BBP :)