RA03TL (ER031) has RF.ER031 is second receiver.(not Antenna)
[DMSS] Second receiver for 2.4GHz Receiver (Diversity anttena Type)
 
DMSS 2.4GHz Second Receiver "RA03TL"
[Dimensions] 6 x 19.5 x 32mm
[Wire Length] Antenna : Coaxial potion/120mm : Antenna potion/25mm
[Weight] 6g
· Mounted telemetry transmission module supports full range of distance. 
· Remote Extension (150mm) included

* Binding (Pairing) process needs to be carried out before use.
Conversion compatibility : 
2.4GHz DMSS receiver mounting remote antenna connector.