Water-resistant according to IPX4UV400 CAT3 polarized lensesOpen speakers, does not interfere with hearing the environmentMusic or sound comes out of both arms of the glasses (stereo)Voice assistant function supportedBuilt-in microphone for phone callsStylish and cool accessoryPerfect combination of Bluetooth headphones and sound glassesHigh-quality hard-shell case made of EVA material with inner material made of microfibreBT Tansmitting distance ~8m (open space)BT Frequency band 2.4GHzBT Radiated transmission power max. 2.5mWBattery: 3.7V 220mAh lithium polymerWorking temperature 0 degrees C ~ +40 degrees CMaterial: Case: EVA; Glasses: TR90