Article number (SKU) - 509266 (black), 509267 (white)
Wearing style - Headband stereo headphones
Ear Coupling - Around-the-ear, circum-aural
Connectivity - Bluetooth 5.2 compliant, class 1, 10 mW (max)
Transmission frequency - 2,402 MHz to 2,480 MHz; GFSK, π/4 DQPSK / 8 DPSK
Supported Profiles - A2DP, AVRCP, HFP
Codecs - SBC, AAC, aptX™, aptX adaptive™
Speaker Type - Dynamic
Transducer principle - 42mm diameter
Speaker frequency range - 6 Hz to 22 kHz
Speaker sensitivity - 106 dB SPL (1 kHz / 0 dB FS)
Total harmonic distortion (THD) - Speaker: 30°C may lead to extended charging times
Battery type - Built-in Lithium-Ion rechargeable batteries 700 mAh
Power Supply - 5 V⎓, 800 mA max, USB charging via USB-C socket
https://www.sennheiser-hearing.com/en-US/p/momentum-4-wireless/