Poly Blackwire C3215 Monaural Headset + Carry Case (Bulk Qty.50) - Mono - Mini-phone (3.5mm), USB Type C - Wired - 32 Ohm - 20 Hz to 20 kHz - Over-the-head, On-ear - Monaural - Ear-cup - 7.4 ft (2.26 m) Cable - Noise Cancelling, Omni-directional Microphone - Noise Canceling - Black