Viken Elantra Series Wireless Bluetooth Headphones Noise Cancelling Headphones w/ Microphone [ Sports / Running / Gym ] (Black and green) "True Viken Elantra Series defines elegance and functionality, and are equipped with Bluetooth 4.0 + EDR in headphones 60% than the wireless competition. Fully exercise-proof: with functional user interface, earpiece design, and a 10-meter working distance, our headphones will let you enjoy music through a variety of activities. Universal device compatibility: the Viken Cool Series Headphones are compatible with most Bluetooth-enabled phones, and reduce external sound Simple-to-use: control all functions of your music (volume, sound, song selection) and calls from your phone via our simple-to-use user interface on the headphones themselves..