DESC: Small Business System 4-Line Accessory Handset further enhances the 4-Line Corded/Cordless with Speakerphone Telephone in that you can take four phone calls without being restricted to you desk. Along with push-to-talk which instantly connects you to an entire network, so you don't have to listen to the dial tone when needing a quick solution for a simple issue, or for having conferences at a moments notice.