We used a magnet ring appearance color: gold (gold color) plating thickness 20-30umum silver (nickel or silver color) 20-30um Black (Parylene black, black epoxy, plating gun black) 20-30um three colors. Technical requirements for surface treatment: Generally, we require the ring surface abrasion resistance and corrosion resistance, salt spray test is generally done 48 hours of basic wear-resistant plating layer can guarantee and can not afford to wear fur or wipe and so on. Gloss on the magnet surface treatment process generally depends on the underlying substrate and the substrate grinding process. Specific surface treatment process will have to see the actual size and process requirements to do the appropriate adjustments. AUO magnet Shenzhen Co., Ltd. Address: Shenzhen Baoan District, Sa Po Wai first industrial zone 20 Block D Tel: 0755-27052468,27052005,27052839 Fax: 0755-27052265 Sales Contact: 13823780428 Mr. Wang E -MAIL: youdamagnet@sina.com Company Website: http: //www.youdamagnet.com