Jabra PRO 900 Midi Boom Replacement Headset for PRO 920 and PRO 930 Base (Base Not Included) Crystal Clear Sound - Digital Signal Processing (DSP) in Jabra audio devices will remove background noise and echo as well as protect the user against sudden high peaks in volume. Wireless Freedom up to 300ft Noise Canceling Microphone reduces unwanted background noise and the noise-canceling microphones reduce unwanted background noise and are ideal in crowded and noisy, open office environments. Safe Tone Peak Stop - Peak Stop technology immediately removes potentially harmful loud sounds or tones before they reach your ears and keeps the sound level within the safe range to protect your hearing.