Features: Designed with super thin speaker which is only one-third of normal speakers, won't press the ears, very comfortable for side sleepers sleeping.? Adopted latest Bluetooth 5.0 technology with forward/backward compatibility to connect to all other Bluetooth enabled media player devices.? Headband design protects you from being disturbed by mess hair and sweat, built-in high-end mic lets you never miss a call during running, yoga or other activities. Built-in 240mAh high-performance battery is charged via USB cable and provides about 8 hours playing time after a 2-2.5 hours full charge. The headband is made from 95% cotton and 5% polyester, with a soft and comfortable feeling. There is a small hole inside the headband for taking out the Bluetooth device, so user can full wash the headband. NOTE: Do not force to pull out the headband to prevent built-in wire being broken. Please take off the headphones when you want to clean headband up.? Specification: Color: Black Material: 95% Cotton + 5% Polyester Bluetooth Version: 5.0 Built-in Battery Capacity: 240mAh Charging Time: 2-2.5hrs Working Time: About 8hrs Note:? Please allow 1-3cm (0.4-1.18") difference due to manual measurement and slight color variation for different display setting. Thank you for your understanding, nice day! Package Includes: 1 x Sleep headphones 1 x Charging cable 1 x User manual ?