Bluetooth version: 4.1 + EDR Bluetooth Profile: HFP 1.6, HSP 1.2, AVRCP 1.4, A2DP 1.2 NOISE REDUCTION: CVC6.0 INTELLIGENT Sound Mode: Stereo Operating Distance: 10 meters Charging time: about 2 hours Standby time: about 100 hours Talk/Playing time: 10 hours Power Source: Built-in Rechargeable Li-ion Battery Size: 40 x 24 x 32 mm / 1.58 x 0.95 x 1.26 inch Net Weight: 16.4 g HOW TO PAIR WITH: 1.Power on & Enter paring mode: Press the "power on" button for 5 seconds until the Blue LED light and Red LED light quickly flash alternatively (with "paring" voice) (Please don't stop pressing the button if you only see the Blue light flashing!!) 2.Use a bluetooth function mobile phone or other bluetooth master device. 3.Try to search the device and connect it(with "connected" voice). 4.Press the "power on" button once while the call is coming / end call. Latest Wireless Bluetooth 4.1 Technology with A2DP stereo music and AptX pure, clear sound, ideal for high quality music. Good noise isolation to create the optimal environment for listening to your favorite tunes, built-in microphone with noise cancellation for clear calling and friends chatting Sweat-proof, light weight and ergonomic design to enhance your comfort; comes with interchangeable earbuds and ear hooks for secure and personal fit when walking or exercising Built-in rechargeable Lithium battery lasts up to 10.5 hours of talk / play time or 175 hours standby, universally compatible with most Bluetooth-enabled phones.