The Spektrum SPM9747 SRXL2 is compatible with all receivers that utilize SRXL2 remote receivers (4-pin connector). It features an integrated antenna design inside the case to provide easy installation and worry-free performance. SRXL2 Technology SRXL2 is a powerful bi-directional communications protocol that improves the speed, security, and richness of data transfer between your radio system and compatible on-board devices such as flight controllers and Smart ESCs. You’ll also enjoy more responsive telemetry that can be customized precisely to your needs. Want to learn more about SRXL2? Visit the SRXL2 Homepage. Integrated Antenna Design The SPM9747 DSMX SRXL2 Remote Receiver features an integrated antenna design that allows for quick and easy installation and eliminates concern for damaging wire antennas. Note: The SPM9747 DSMX SRXL2 Remote Receiver is not compatible with receivers that use 3-wire remote receivers. The main receiver unit must be compatible with a 4-wire SRXL2 remote receiver. The SPM9747 is only compatible with receivers that feature SRXL2 such as the AR637T and AR6610T receivers.