Dell Pro WL5024 Wireless ANC Headset (520-BBGM) - Speaker Size: 40mm, Frequency Response: 20Hz - 20kHz, Noise cancellation (microphone): AI Up-Link Noise Cancellation, Microphone Type: 5 (2 analog, AI Beamforming&4 Hybrid ANC), Form Factor: On-Ear, Connectivity: Bluetooth, USB-C (plug in for fast charging), Battery Capacity: 750 mAH, Talk/Listening Time: Up to 78 Hrs