This SAE Standard specifies system requirements for an on-board vehicle-to-vehicle (V2V) safety communications system for light vehicles and public safety vehicles ¹ , including standards profiles, functional requirements, and performance requirements. The system is capable of transmitting and receiving the SAE J2735-defined basic safety message (BSM) over a PC5 Sidelink V2X (mode 4) communications link as defined in ETSI Release 14^2,3. The system uses Institute of Electrical and Electronics Engineers (IEEE) 1609 standards for network and transport layer communciations, as well as security.