W820BT bluetooth Headphone Wireless Over-Ear Hifi Noise Isolation Stereo Headset With Mic for Phone Tablet 01 COLOR SPECIFICATIONSDriver unit: 40 mm NdFeB driversbluetooth version: bluetooth V4.1Supported profiles: HFP, HSP, A2DP, AVRCPFrequency Response: 20 - 20,000 Hz - Impedance: 32ΩBattery Capacity: 1340m - Ah, 3.7VCharge Time: 4hrs - Standby Time: 80hrs - Sound pressure level: 100 d - BWeight: 0.26kg FEATURESEdifier’s around-the-ear closed back headphones are known for their comfort as well as their sound quality. With the W820BT experience all-day comfort with thanks to the foam padding on the ear cups that shapes to the area around your ear. Strong Flexible Steel Headband - Adjust the headband’s tightness by bending out or bending in the headband. The W820BT has adjustable sides to fit the shape of your head to achieve ideal comfort. Listen for 80-hours straight with Edifier’s headphones. - If you prefer having using a traditional headphone cable, one is packaged in the box to let you switch between wireless and wired. Keep your music on a loop even when the battery runs low - The W820BT comes with the AUX-in cable for extended in passive mode. - Continue using the headphones without worries. Easy storage - With rotate designed ear cups that can be folded easily, EDIFIER W820BT is a smart choice for traveling and outdoor activities.