The LTE-21V is an optional communicator that snaps directly onto the VISTA21iPLTE panel, enabling dual path reporting. It is part of Resideo�s long-lasting family of LTE products that will help grow your business for years to come.Resideo�s end-to-end system solution combines hardware and cloud services to streamline your business and is quality tested, warrantied and agency listed to offer superior experiences compared to any other service provider.