Product details of NIA S4000 Wireless BT Over ear Hi-Fi Stereo Headphones Function: Wireless And Wired Connection Audio Interface: 3.5mm Frequency: 20Hz-20KHz Impedance: 32Ω Driver Unit: 40MM HD Driver Unit Battery: 250mAh Transmission Distance: 10M Standby Time 200Hours Charging Time 2 Hours Working Time 6-8 Hours Equipped with ultra powerful 40mm drivers, our Wireless Over Ear Headphones generate truly earth trembling bass, clear mid-tones and provide exceptionally clear music and audio reproduction with a super wide 20-20,000Hz frequency response! Designed for incredible audio on the move, our Foldable Wireless Headphones are Bluetooth 5.0 enabled, for up to 33 feet of immersive, wireless music, instant one-touch call handling and with an inbuilt 87.5-108 MHz memory function FM digital radio and proprietary control app, our Wireless Bluetooth Headphones provide a truly unmatched audio experience! Comfortable, lightweight and ergonomic, our Headphones use the finest super soft, memory protein ear pads for outstanding noise isolation together with precise, easy access, ear cup mounted fingertip controls. With a reinforced, PU-leather, fully adjustable headband with beautiful, stitched detailing together with solid, chromed, foldable ear cups, our Bluetooth Wireless Headset can easily withstand the toughest everyday use! Specifications of NIA S4000 Wireless BT Over ear Hi-Fi Stereo Headphones SKU 232586514_PK-1451934751 What’s in the box 1 X NIA S4000 Bluetooth Headphones