The Poly (Plantronics) CS540 Spare Convertible Wireless Headset 86179-01 is a sleek black headset with on-the-ear ear-pad design. It features volume control, noise cancellation, and a built-in microphone with a boom type for clear communication. Designed by Plantronics, this headset is compatible with the CS540 model, perfect for users looking for a high-quality, versatile headset for home telephones or other communication devices.