Trim Position Triple Indicator, Rudder, Aileron, Elevator GE DJ-3 Model 8DJ3ECC Grumman The manual covers instruments that

The manual covers instruments that were eventually used in aircraft of the Air Corps US Army and Air Force US Army during WWII

and the front page of the Collins sales brochure

True Airspeed Indicator

and the reflected signal is received on a separate receiver antenna

It has a serial # prefix of AF57

Trim Position Triple Indicator, Rudder, Aileron, Elevator GE DJ-3 Model 8DJ3ECC Grumman The manual covers instruments thatThis is a triple Trim Tab Position Indicator, made by General Electric, Type DJ 3, Model 8DJ3ECC, likely from the 1950's and used in US Navy aircraft judging from the blue green of some of its lettering and the presence of a USN stock # (R88 I) etched on the top edge of the case. Measures 3. 25in diameter and ~2. 75in deep. It is in exceptional condition given its age. The dial markings are clear and the glass and case are intact.