Never miss a customer when door opens for business entryKoostone door sensor always monitors door opening, you will be reminded if someone open the door. The door chime would be the most conscientious and committed worker in your shop.5 Levels Volume Control and 400ft Wireless Range5 levels volume on each ringtone, allow you lower voice to silence or turn the volume up to 120dB.You can place the Receiver almost anywhere in your home/shop because it has a 400ft wireless range.
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