The casing of the band is made of plastic with a glossy metallic paint on the surface. Essentially, it is a plastic product. Wearing it together with hard metal jewelry (such as metal bracelets or irregular metal jewelry) or mineral jewelry (such as jade or crystal bracelets) can cause scratches, dents, abrasions, or paint loss on the band's surface. Therefore, it is not recommended to wear the band with metal or mineral jewelry. It's best to wear them on separate wrists.