Silipower True Wireless Earbuds, Bluetooth Headphones, in-Ear Sweat-Proof Stereo Earphones with Mic, Portable Charging Case Super Sound Quality with V4.1+EDR - Bluetooth 4.1 true wireless headphones with advanced audio technology. The built-in high-quality sound chip provides you with the crystal clear high & low frequencies. Two interconnection pieces are creating great stereo and excellent bass surrounding sound. Durable and Standby Time - Built-in 50 mAh Lithium Polymer Battery, Enjoy about up to 3 Hours of Premium Quality Talk/Play Time (Full Charge approximately 1-2 hours), up to 40 hours standby time. 430mAh Capacity Charging Case Can Provide 3-4 Times Longer Charge by USB. Ergonomic Design - Comfortable and Secure in-ear Earbuds, Soft Material to Protect Ears, Make Your Phone Call and Music Time More Comfortable. Ear Hook Design Can Be Perfect for Sports, Jogging & Gym Exercise, Watching TV, or Sleep. 3 sizes of ear caps can fit all kinds of people. Single or Dual Wireless Earbuds - true wireless earbuds are a multi-point connection. This pair of true wireless Bluetooth earbuds can be used as one single earbud to keep an ear open for the traffic or use as a pair to enjoy music. They are compatible with hundreds of brands and other devices with Bluetooth function. Connects up to the 30 Ft in the open space, make your earbuds extraordinary. Multifunction and Ultimate Compatibility - Technology with voice notification of incoming calls. High dynamic range built-in microphone to make calls, with buttons on the earbuds allows you to Play/Pause on your favorite music tracks as well as Answer/Hang up phone call without reaching your phone. It is easier for you to handle your calls while driving. Our earbuds are compatible with hundreds of different mobile phone brands. The first true wireless earphones that satisfy all your needs. 1 x Pair Wireless Bluetooth Earbuds (Left &amp; Right) 3 x Pair of Ear Cap (2 Pair of S/ 1 and a Pair of M) 1 x 430 mAh Charging Case 1 x USB Cable 1 x User Manual Weight:4g/0.14 oz (Earbuds); 70g/2.5 oz (Charging Box) Bluetooth Version: 4.1+EDR Working Range: 33ft/10m Battery of Headset: 50mAH Battery of Charging Box: 430 mAh Earphone Charging time: 45-60 minutes Charging Case Charging time: Approximately 2 hours Dual (2 Earphones) Mode or Single Ear Mode and Binaural Mode PS: (L) Earphone is the master, (R) Earphone is the slave. Only the master Earphone (L) has sound during phone calls. Use during driving will help to keep your safe for a hands-free experience.