This is the Futaba R603GF 2.4GHz FHSS Sport 3-Channel Receiver.
FEATURES: Flexible coaxial antenna that's easy to position inside a model for
ideal reception
Compatible with the Futaba 2PL and 3PL
INCLUDES: Futaba R603GF 2.4GHz FHSS Sport 3-Channel Receiver
REQUIRES: Installing in model and connecting battery and servos
Linking to Futaba 2PL or 3PL 2.4GHz transmitter
SPECS: Power Requirement: 4.8V or 7.4V NiCd battery
Size: 1.02 x 1.53 x 0.39" (26 x 39 x 10mm) excluding area where
servos plug in
Weight: 0.28oz (8g)