Bluetooth 5.1 headphones EPSILION BT MT3591 with built-in microphone, FM radio, and microSD card reader. These headphones feature excellent sound quality and very comfortable operation. The headphones are powered by a durable lithium-polymer battery. Music playback time on a full charge is 10 hours, thanks to the energy-efficient Bluetooth 5.1 technology. The range of the headphones is up to 10m, so during use, the smartphone can be placed in a safe location. EPSILION BT are compatible with computers, smartphones, and TVs equipped with a Bluetooth interface. Thanks to the placement of the call answer/end button and the volume control and music management buttons, operating the EPSILION BT device becomes extremely simple and intuitive. Headphones ready for any occasion An additional advantage of the MT3591 is the ability to use them as wired headphones (3.5mm jack input). This function works perfectly in case of a dead battery. In addition, EPSILION BT can act as an independent sound source; just insert a microSD memory card (up to 64GB) with your favorite music or turn on the FM radio to listen to available radio stations. microUSB port The headphones are equipped with a microUSB port. With one charger, you can charge your smartphone and the wireless headphones EPSILION BT. If necessary, the headphones can be folded and stored in a bag to take up as little space as possible. Technical specifications: Wireless stereo headphones Bluetooth V5.1 interface with EDR FM-radio 87-108MHz MP3 player with microSD card up to 64GB Built-in high-quality microphone and speakers Support for standards: A2DP, HSP, AVRCP Frequency response: 20Hz – 20kHz 3.5mm jack LINE IN port for wired mode (cable not included) Foldable design Battery: Li-Polymer up to 10 hours of operation Charging time: approx. 4 hours Power (W) 15 mW*2 Impedance (Ω): 32 Ω Sensitivity (dB): 103 ± 3dB S.P.L at 1KHZ Resistance (Ω): not required for headphones Weight: 152g