ShoreTel Compatible Plantronics CS540 VoIP Wireless Headset Bundle with Electronic Remote Answer|End and Ring Alert (EHS) for ShoreTel IP 100 212 230 230G 265 420 530 560 560G 565 565G Bundle of 2 items - Plantronics CS540 Wireless Headset and ShoreTel compatible ring alert interface cable Compatible ShoreTel Phones: IP100, IP212K, IP230, IP230G, IP265, IP420, IP530, IP560, IP560G, IP565G, 565, 565G Weighing 21 grams makes the CS540 the lightest in the industry 7 hours of talk time gets you through the busiest of work days 350+ feet of distance gives you mobility throughout your office