Like New Never Used: Whether at home or on the go The wi-c310 headphones deliver great sound with up to 15 hours of battery life1 A versatile and practical design with 9mm driver units for clear sound and lightweight design for maximum comfort make these a great choice for wireless headphones. Frequency Response (Bluetooth Communication): 20 Hz–20,000 Hz (44.1 kHz Sampling), Magnet: Neodymium, Frequency Range: 2.4 GHz band (2.4000 GHz–2.4835 GHz). Features & details Wireless Audio with Bluetooth technology Product Note : If the size of the earbud tips does not match the size of your ear canals or the headset is not worn properly in your ears, you may not obtain the correct sound qualities or call performance. Change the earbud tips to ones that fit more snugly in your ears Up to 15 hours of battery life 9mm driver units for crisp, clear sound Flexible and lightweight cables Hands-free calling and voice assistant compatible In The Box USB Type-C Cable (USB-A to USB-C) (approx 20 cm)