Hi-Res Audio Certified: Enjoy more detailed music thanks to Edifier W820NB's 40 mm dynamic drivers. High-resolution Audio compatible. Supported Audio Format(s) - SBC, AAC. Hi-Res Audio Certified: Enjoy more detailed music thanks to Edifier W820NB's 40 mm dynamic drivers. High-resolution Audio compatible. Supported Audio Format(s) - SBC, AAC. Powerful Battery: Up to 49 hours of battery lifeon a single charge keeps you listening instead of charging, just focused on your work or travel. Clear Hand-Free Calling: Built-in Mics with DNN (deep neural network) noise cancellation for superior call quality With Multi-mode: Ambient sound mode let you control what you hear. Game mode gives you a low latency and immersive gaming experience.