Futaba 4PLS 4-Channel 2.4GHz T-FHSS Radio Transmitter On Ebay
https://www.ebay.com/itm/Futaba-4PLS-4-Channel-2-4GHz-T-FHSS-Radio-Transmitter-No-Receiver/283875201877?
https://www.ebay.com/itm/Futaba-4PLS-4-Channel-2-4GHz-T-FHSS-Radio-Transmitter-No-Receiver/283875201877?