This headset training bundle comes with a "Y-Training Splitter Cord" #27019-03 and Digital Headset Adapter that connects the two XS 825 headsets to a single phone to perform agent training, supervisory, coaching, multi-users on one call. Use it in help desk, office or contact center or anywhere you need to have 2 people on a call on a deskphone What's in the box: â Item A- 2 units XS 825 Mono Headsets â Item B- Universal Telephone Headset Adapter InteliCordâ Item C- Global Teck Supervisory Splitter Y-cord Mitel Compatible Phones Yealink Phone models:à T48S, T48G, T46S, T46G, T42S, T42G, T41S, T41P, T40G, T40P, T29G, T27G, T27P, T52S, T54S, T56A, T58V Compatible NEC Phones Elite Series, and Mark II Series. (Models: DTP-8D, DTP-16, DTP-16D, DTP-32D, DTU-8D, DTU-16, DTU-32, DTU-32D) DTerm IP, DTerm i-Series, DTerm Series E, DTP, DTR, DTH, DTU, DTL DSX Series, ETJ Series, ETZ Series. Polycom Phones: VVX and Soundpoint IP deskphones, Shoretel Compatible Phones Shoretel IP230, IP265, IP565Shoretel IP480, IP530, IP655 Other Shoretel models: Requires RJ-9 headset jack Cisco Compatible Phones 7900 Series Cisco (7940's, 7960's, 7965, etc) 6900 Series - 6921, 6941, 6945, 6961 8900 Series 8811, 8841, 8845, 8851, 8861, 8865, 8900 Series - 8941, 8945, 8961 9900 series -9951, 9971 Other Cisco models: Require RJ-9 headset jack port Nortel Compatible Phones Nortel and Norstar, phones with RJ9/RJ22 Headset Port