A multi-dielectric film including at least one first dielectric film that is a composite film made of zirconium-hafnium-oxide and at least one second dielectric film that is a metal oxide film made of amorphous metal oxide. A relation between a diameter A of said ball and an axial width W of said inner ring and said outer ring satisfies AW\u22670. A powerful magnet is secured within the base of the cup providing magnetic attraction and selective positioning and removal attachment on to any ferrous metal club head face.