Oem is accepted Free sample is available Visit factory is welcomed Specifications of soft magnetic power core: 1.Type: toroidal core/ee core/ec core/pq core/uu core/ei core/efd core/rm core/pot core/epc core. 2.Compostion: mn-zn ferrite power. 3.Grade: rm2.3kd, rm3.3kd. 4.Environment: rohs. 5.Certification: iso9001:2000. 6.Advantages: Fast and large batch supply capacity. Low loss and high frequency. Competitive price.