This is the Eagle Tree Systems OSD Pro Expander. FEATURES: Fully configurable Provides graphics, voice announcements, alarms, acoustic variometer with total energy compensation, Home Arrow, Return to Home, Failsafe, "RADAR", waypoints, a flight simulator for testing and many other features INCLUDES: One OSD Pro Five Male to Male Servo Connectors One Manual REQUIRES: Eagle Tree Systems eLogger V3 or Data Recorder cnh 6/26/09 ir/jxs