DOQAUS specializes in the design and manufacture of premium audio solutions. We pursue features of products and customer experience value each feedback and improve outcomes timely to meet customers needs. Since we established seeking perfect sound quality we have designed products that music lovers would desire and have been sold worldwide. Comfortable to Wear The soft memory protein ear pads and the adjustable padded headband ensure first-class wearing comfort even for long listening periods. You don t need to fear an earache while you wear it for a long time since the lightweight headphones weigh only 230g (0.5 lb) Great Compatibility It supports devices with a 3.5mm audio jack such as iPad Chromebook Switch Smartphones Computer Kindle MP3/4 Fire Tablet Study Tablets Laptops PC etc. PRODUCT INFORMATION Drive unit: Φ40mm Impedance: 32Ω±15% Frequency response: 20HZ-20KHZ Sensitivity: 74DB 85DB 94DB Rated power: 10mW Maximum power: 30mW Audio cable length: 1.4m±0.1