Vbet VT2000NC-D (USB PORT) Two ears wearing, enhance comfort and clarity The Ultra noise canceling Mic filters 80% background noise Noise Cancelling Microphone with Foam Protector Broad Band audio frequency Hearing protection with Active ProtectionTM technology Ultra FlexTM MIC wires,boom rotation>20k times Teflon washer increases stability and ensures optimal durability Optimized for noisy official users and call center users