This kit contains two Enphase products:1.Enphase Energy System Communications Kit (COMMS-KIT-01)2.Enphase Mobile Connect Cellular Modem CELLMODEM-M1-06-SP-05 with T-Mobile SIMThe Enphase Communications Kit (COMMS-KIT-01) contains a wireless USB adapter that facilitates continuous communication between IQ Gateway/IQ Combiner/Envoy-S Metered, IQ Gateway S Metered/IQ Gateway S combiner box, IQ Battery 3/3T/10/10T and IQ System Controller 1/2.The Enphase Mobile Connect Cellular Modem delivers easy, reliable networking for Enphase Energy Systems. CELLMODEM-M1-06-SP-05 is an LTE CAT M1 cellular modem. It includes a prepaid 5-year data plan and acts as a backup communication path for an Enphase Energy System in case the Wi-Fi or Ethernet connectivity fails.Note: This product requires installation by a certified installer. At checkout, you can request matching to an installer in your area.