This is a single-ear earphone that allows you to enjoy music with a sense of openness without blocking your ears. Even while listening to music, you can clearly hear the surrounding ambient sounds, so you can listen to your favorite music while working in the office. The main body is very light and thin, and does not cause pain even after long hours of use. Specifications: Color: Black Program: For Airoha1523u Bluetooth: 5.2 Standby Time: 130-140H Battery Capacity: 70mAh Transmission Distance: 32.8 feet (10 m) Charging Interface: Micro USB Talk Time: 3.5 - 4.5 H Charging Voltage: DC 5V *This product is offered at an inexpensive and reasonable price. Please refrain from purchasing if you are particular about perfection and quality.