該產品用於特種空心杯電機，具備以下特點：
These manetic rings are mainly used in the coreless brushless DC motors, which have following features:
1. 產品性能穩定，一致性好。
Have stable and good consistence in magnetic properties.
2. 產品精度高，平衡量小。尺寸公差和形位公差都在5絲以內，可以根據客戶要求定製2絲以內的產品。
High precision: All products' dimensional and geometric tolerance are controlled within 0.05mm, some special products are within 0.02mm according to customer's requirement.
3. 耐腐蝕性好，可以做到2mg/cm^2的低失重，表面處理鹽霧試驗要求可以達到72H以上。
Good corrosion resistance: weight lost less than 2mm/cm^2, and surface coating can reach 72H above.
