Rechargeable: Comes with a charging wire and works for eight hours on a 2.5 hour charge. Sleeping mask: Get a Bluetooth headphones sleep eye mask in black or grey! Material: Made using a soft, cosy material (90% polyester, 10% cotton). Bluetooth: With Bluetooth technology so you can connect it up to your smartphone. Music: Listen to music, audiobooks, ASMR and other calming audio whilst you nod off. Connectivity: Connects from up to 20m away from your device. | Bluetooth Headphones Sleep Eye Mask - Black | Wowcher