English 
Connects to PC and Mac ® via USB
Ideal for Users with extensive PC communication and multimedia; featuring smart sensor technology
Audio performance Dynamic EQ, microphone frequency response 100 Hz–8kHz optimal for wideband voice telephony (up to 6,800 Hz), hi-fi stereo output from 20 Hz-20 kHz (C520 only), enhanced digital signal processing (DSP), noise- canceling microphone
Hearing protection SoundGuard®: Acoustic limiting for protection against sounds above 118 dBa
Models C510 (monaural); C520 (stereo): UC Standard version built for UC applications and softphones from Avaya®, Cisco®, Skype® and more* C510-M (monaural); C520-M (stereo): Certified for Skype for Business and Optimized for Microsoft® Lync®
* Download the latest release of Plantronics Hub software to get one-touch call answer/end with these softphones.