What is the operating frequency for electronic shelf labels (esl)?

What is the operating frequency for electronic shelf labels (esl)?

What is the operating frequency for electronic shelf labels (esl)?
As you known .we are professional electronic labels manufacturers.we have different solutions for different fields, such as supermarket , warehousing ,meeting room, digital intelligent medical care and so on.
So we have Bluetooth 2.4GHz operating frequency ,Rf 433Hz operating frequency ,NFC 13.56Mhz operating frequency and Wifi 802.11.b/g/n operating frequency.
Welcome to contact with us , we will provide detail solution for you .https://www.eslmfg.com/products-index.htm
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