Plantronics WH300 spare over-the-head, monaural, DECT 6.0 headset for the W720, W710, CS520 or CS510.The Plantronics WH300 is the replacement/spare monaural headset for the Plantronics Savi and CS500 series wireless headset systems. This is the spare headset if you lost or broke your Plantronics headset. It easily syncs up with your – existing W720, W710, CS520 or CS510 wireless charging bases. The headset comes with leatherette ear cushion that eliminates background noise. It is easy and Comfortable to wear. This part will not function without a charging base and cradle.