Devia M4 are in-ear Bluetooth 5.2 TWS earphones with a charging box. The earphones support TWS (True Wireless Stereo) technology – both earphones connect to each other to create a wireless stereo set. A portable box with a built-in battery, in addition to the charging function, allows you to safely store the headphones in your pocket, bag or backpack. Free your hands and listen to music, Internet radio, while working, walking, training or driving a car. Devia M4 TWS earphones are an ideal solution for users of smartphones, computers, notebooks, tablets and other Bluetooth-enabled devices. They are compatible with most Android and iOS devices. The earphones also have a microphone, so you can easily make voice calls. The duration of calls/listening to music on a full charge is approximately 300 minutes (depending on the volume level), thanks to the use of energy-saving Bluetooth 5.2 technology.