The product is a pack of 20 pieces of TOJOIN clip-on ferrite ring cores with a diameter of 7mm and black color. These cores are made of Ni-Zn ferrite material and are applicable in the frequency range of 1MHz-1000MHz. They are designed for various electronic components such as phones, TVs, speakers, USB radios, and audio devices. The cores come in a box packaging and are manufactured in China. Ideal for use as passive components in electrical equipment and supplies, these ferrite cores can help reduce electromagnetic interference and improve signal quality.
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