Technical indicators:

Category: airtight dynamic
Cell Diameter: Ø45 mm CCAW (Copper Clad Aluminum Wire)
Frequency Response: 15 ~ 28,000Hz
Sensitivity: 99 dB/mW
Impedance: 38 Ω
Battery Type: DC 3.7 V Lithium Polymer Rechargeable Battery
Battery consumption / life: about 50 hours of continuous use
Charging time: about 3.5 hours
Weight: 307 grams (excluding wires and plugs)
Leads: Interchangeable 1.2m gold-plated stereo mini-plug cable (L-shaped)
Standard: 30cm long USB charging cable (USB Type-A / USB Type-C), protective bag

ATH-M50xBT2 Specifications (Microphone):

Category: MEMS
Directivity: omnidirectional directivity
Open circuit sensitivity: -38 dB (1V/Pa at 1 kHz)
Frequency Response: 80 ~ 15,000 Hz
ATH-M50xBT2 Bluetooth Specifications: Transmission System Method
Bluetooth (Bluetooth): Ver.5.0
RF output power: 5.1 mW EIRP (max)
Effective working distance: up to 10 meters in good condition
Operating frequency: 2.4GHz band (2.402GHz ~ 2.480GHz)
Transmission system: GFSK, Pi/4DQPSK, 8DPSK
Spread Spectrum Method: FHSS
Bluetooth Profile: A2DP, AVRCP, HFP, HSP
Audio codec: LDAC, AAC, SBC
Content Protection: SCMS-T
Frequency Range:
20 ~ 40,000 Hz (using LDAC 96 kHz sample rate, 990 kbps rate)
20 ~ 20,000 Hz (using 44.1 kHz sampling rate)

Specifications: