PLANTRONICS CS351N Monaural SupraPlus Wireless Professional Headset System Noise-Canceling with HL10 Lifter - Office professionals with phone-intensive responsibilities can now move about the office in unmatched comfort and with premium audio quality. Built on digitally-encrypted DECT 6.0 technology, the Plantronics SupraPlus Wireless Professional Headset System combines the clarity of traditional corded technology with the mobility of wireless, so conversations can continue up to 300 feet from a desk phone.