Plantronics CS55 wireless headset use the new 1.9 GHz voice-dedicated frequency which provides users with strong sound quality for optimal voice and hearing clarity. Using the new voice-dedicated 1.9 GHz DECT standard frequency, business professionals don't have to worry about interference from nearby Wi-Fi networks, cordless telephones, and other wireless office equipment common on other frequencies. The result is a less crowded radio frequency that provides superior audio clarity with no interruptions.Digitcom.ca, Telephone Systems, VoIP.
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