Thickness is only one-third of the average speaker, which is very comfortable for sleepers. True HD HIFI sound featuring latest Bluetooth V-5.2 technology that produce great sound quality, bluetooth can pair your any Smartphones Tablets easily.Compatible with Android and Ios.It is the best gift for family or friends on travel and airplane in Festivals. Upgrade usb chargeable battery, Built-in 240mAh high-performance battery, Charge about 2-2.5 hours provide more than 9 hours playing time, wont be waked up at night,enough to support the whole night.If you fall asleep with it on and the battery runs down , this bluetooth eyemask won't beeps to wakes you up. you will have a very good sleeping. Block light to make your sleep better, allows you to listen to music without wearing additional headphones,which make you fall asleep faster.Extra cushion makes eye mask and nose touch better, which can be completely shaded. Best for frequent flyers to sleep on long flights or sensitive sleepers (insomnia) who dislike glaring lights in any occasions.Sleep in a light blocked world whenever and wherever.Perfect for air travel, relaxation, meditation, insomnia. Bluetooth sleep mask is made from elvet and elastic cotton, and provide a soft and comfortable feeling. Fabric liner separated from stitching is not defective,it is the place to take out the bluetooth module, so you can full wash the eye mask.You don't have to worry about it shrinking and deforming. Velcro is adjustable, also fit big heads,sleep eye mask can be adjusted according to the size of the head.The delicate wiring connected to the speakers that go from ear to ear is very sturdy, you can adjust adjust the position of the speakers for your ears to hear more clearly.