Wheelerz 25W Trolley...

Frequency Response Range: 20-20000 HzActive Noise-Cancellation: YesBuilt-in Microphone: YesBattery Capacity: 55 mAh

BT 5.1 technology ensures higher data transfer speed, more stable and fast connection, and lower power consumptionTrue wireless dual-ear design, left and right earphone channels are separated. It can be used solely or in pairsAuto power on and fast pairing between left and right earbuds once opening the charging case lidTouch control design, no more pressure on your ears. Easy to control music and calls, and activate voice assistantBuilt-in Mic on both earbuds with noise reduction enables hands-free call and delivers clearer talking sound in stereo mode

Has engineered the precise, impressive sound found in big venues around the worldHeadphones reproduce that same sound, punching out bass that?s both deep and powerfulStream your favourite tunes in super high quality thanks to Bluetooth 5.0Built-in battery provides 16 hours of playing time, that can be quickly recharged in 2 hours with the type C cable15-minute recharge gets you 1 hour of playback

Driver sensitivity range is about 1kHz/1mW (dB) with impedance 14 ohmsDynamic frequency response range is about 20Hz?20 kHzWith up to 25 hours 5 hours from the earbuds and 15 hours from the case of battery lifeBluetooth frequency range is up to 2.4-2.4835 GHzTransmitted modulations are GFSK, ?/4 DQPSK, 8DPSK and 55mAh 3.7V battery