GN NETCOM 935-15-509-205 Jabra Pro Landline Telephone Accessory Dual Connectivity - Dual connectivity technology lets you manage phone calls from several different devices, with one single headset. You get greater flexibility and enhanced user experience 12-Hour Battery Life - A wireless audio device would not be a useful tool without an incredible battery life. Even with so much performance packed into such a small space, it still lasts up to 12 hours on a single charge HD Voice - High quality audio for crystal clear conversations Enjoy high-definition sound with HD Voice and get crystal clear, intelligible communication