GRDE Wireless Stereo Bluetooth Neckband Hands-Free Headsets Headphones for Smartphones & Tablets - Black Unique wearing style: light weight, flexible neckband design with crystal clear sound. With 170mAh capacity, it offers 10 hours talk time, 8 hours play time, and 288 hours standby time CSR 8635 bluetooth 4.0: perfect for on-the-go usage, roam away from your connected cellphone (without walls/doors) and still keep the connection. And when you've got your mobile phone with you, you can leave within 10 meters Built-in microphone & vibrating call alert: make and take calls safely and easily, no matter what you're doing. Voice guidance: easily to operate the headset. Call, Answer and Redial the last number Battery status alert: to check the battery status, press and hold the Volume DOWN button for a second. There are 3 levels of battery status: battery high,battery medium and battery low.(The battery status indicator of the headset will appear on the iPhone screen)