Bluetooth 4.1 Sport Headphones In-Ear Earbuds Mic Wireless Stereo Headset New, unused item in its original packaging, which was opened for inspection purposes. Color: Green Bluetooth version: Bluetooth 4.1 Playing time: approx. 2.5 hours Charging time: approx. 1.5 h Battery: 3.7V/55mAh lithium-ion battery Radio range: 10m Frequency response: 20Hz - 20KHz All trademarks, logos, product and company names are subject to the rights of their respective companies and are used only in the product description as part of the product information.