Advanced Bluetooth 5.0 Stereo Sound : Our sleep headphones feature updated BLUETOOTH 5.0 technology, which provides stable connectivity and smooth high-speed, long-distance transmission with low consumption for a great stereo sound experience. You can listen to soft music without wearing additional headphones. High quality adjustable built-in speaker and microphone for clear hands-free calling. Innovative 3D contour design and no pressure on your eyes : This Bluetooth sleep mask is designed with breathable material and comfortable feelings. This mask also adopts 3D ERGONOMIC TECHNOLOGY for the eye area and blocks 100% of light to create an absolute dark area. The sleep headphones eye mask perfectly solves the tightness of the silk eye mask, brings you a comfortable and long-lasting sleep. 10 hours continuous playback : our Bluetooth headset masks offer upgraded USB rechargeable battery, charging about 2-2.5 hours provides over 10 hours of playing time. The Bluetooth mask will not beep to wake you up, you will sleep very well. Timer Function : Our sleep headphones also have a 1 or 2 hour auto-off timer, the Bluetooth headphones can play all night or automatically turn off depending on your different needs. Press and hold the middle button to set the desired mode. Breathable and washable : The 3D wireless eye mask with new design Velcro strap can be adjusted according to head size from 20 to 28 inches. Adjustable non-slip hook and loop closure allows for a truly custom fit for Americans and fits most people (men, women, children). The Bluetooth control module can be removed from the sleep mask, then you can wash the mask.