Note there have a small hole , the headphone can be taken off, so that you can wash the hat. taken it out before you wash the hat. Features Item Name: Hat Heatphone Material: Woolen Yarn + ABS Bluetooth-Compatible Version: 5.0 Power Supply: Built-in 180Mah Lithium BatteryFeatures: Bluetooth-Compatible, Comfortable, Warm Size: 22.5cm x 21.5cm(Approx.) Description Support Bluetooth-Compatible & Bluetooth-Compatible music. Low loss of high-quality stereo sound. Charging through USB cable, long standby time. Package included 1 x Hat Headset 1 x Charging Cable 1 x User Manual Note: 1.We don't offer retail package,but we will pack it well before shipped out. 2.Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you buy. 3.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you