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Connecting Manually (pairing with another phone or re-pairing)
1. From the mobile phone’s Settings menu, turn on Bluetooth.
2. With the ABC-123’s power off, press and hold the Call button and slide the Power switch to the ON position to turn it on.
3. The blue Indicator lamp turns on, and the ABC-123 enters Search mode.
4. From the mobile phone, select ABC CD1234 to connect.
5. A voice message will indicate that the connection is completed.

Multiple Connections
The ABC-123 can be connected to a mobile phone and a PC simultaneously.
The ABC-123 can be connected to an additional device while it is already connected to a device.
1. With the ABC-123’s power off, press and hold the Call button and slide the Power switch to the ON position to turn it on.
2. The blue Indicator lamp turns on, and the ABC-123 enters Search mode.
3. From the mobile phone or device list, select ABC CD1234 to connect.
4. A voice message will indicate that the connection is completed. This device becomes the “Main Connected Device.”
5. Try to connect to ABC-123 using a previously connected device. This device becomes the “Sub Connected Device.”
NOTE: If the ABC-123 is simultaneously connected to two devices, the device that was connected most recently (or, as in the example above, a new connection verses a previous connection) is the Main Connected Device. The main functions work based on the Main Connected Device.

У кого-то есть варианты, что такое ABC-123? Это какое-то устройство... Телефон кнопочного типа, или пульт, или устройство ввода букв и цифр. Это весь текст, который есть.