This is the Futaba R603FF 2.4GHz FASST 3-Channel Receiver.
used in the 2.4GHz 3PM Pistol Grip Radio.
FEATURES: Incredibly small and lightweight
Futaba Advanced Spread Spectrum Technology (FASST) allows receiver to
process information at eight times the resolution of standard
systems for unsurpassed control and smooth servo travel
One year limited waranty
SPECS: Reception Antenna: External - single antenna
Power Requirement: 6V NiCd battery
Size: 1.5 x 1 x .55" (39 x 26 x 14mm)
Weight .45oz (12.8g)