40mm is the driver size. Range of dynamic frequency response: 20 Hz–20 kHz 96 dB is the sensitivity. SPL maximum: 111 dB Sensitivity of the microphone at 1 kHz dB v/pa: -42 Power transmitted wirelessly: 0–4 dBm Modulations for wireless transmission: GFSK, n/4DQPSK, and 8DPSK Frequency range for wireless: 2.402GHz-2.48GHz HFP v1.6, HSP v1.2, A2DP v1.2, and AVRCP v1.4 are wireless profiles. 320 hm of impedance Version 5.3 for wireless Type of battery: 250mAh polymer Li-ion battery Two hours are needed for charging. Up to six hours of music playback with BT turned on