1. Power on the headphones by pressing and holding the power button until the LED display lights up.
2. Activate Bluetooth on your device and select the XUNDD X39 from the list of available devices.
3. Adjust the fit of the headphones for maximum comfort.
4. To answer or end a call, simply press the multifunction button on the headphones.
5. To turn off the headphones, press and hold the power button again until the LED display turns off.
6. For optimal performance, ensure to charge the headphones regularly and keep them clean and free from debris.
Keywords: XUNDD X39, LED DISPLAY, CTO C AIRPORT 2 PRO, ANC, Bluetooth, headphones, active noise cancellation, wireless, high-quality sound, comfort.