Avantree Opera 35Hrs Comfortable Wireless Headphone review. 1. Finally, the long-awaited Instant Avantree Opera 35Hrs Comfortable Wireless Headphone has arrived. It took about two days to arrive, and it was delivered in a sturdy paper box in excellent packaging. 2. If you open the box, there is a charger and usb port I'm happy that it's all shipped in clean condition. 3. Finally, the Avantree Op..
