Wireless, on-the-go design delivers the same sonic signature as the wired ATH-M20x professional studio headphones 40 mm drivers with rare earth magnets and copper-clad aluminum wire voice coils are tuned for enhanced low-frequency performance Low latency mode improves synchronicity between audio and video for smooth streaming and gaming Multipoint pairing function allows you to stay connected to two Bluetooth devices at once Up to 60 hours of continuous use on a full charge and up to 3 hours of use on a 10-minute rapid charge (via USB-C connection) This pre-owned or refurbished product has been professionally inspected and tested to work and look like new. How a product becomes part of Amazon Renewed, your destination for pre-owned, refurbished products: A customer buys a new product and returns it or trades it in for a newer or different model. That product is inspected and tested to work and look like new by Amazon-qualified suppliers. Then, the product is sold as an Amazon Renewed product on Amazon. If not satisfied with the purchase, renewed products are eligible for replacement or refund under the Amazon Renewed Guarantee.