KO Propo KR-211FH FHSS receiver
The KO Propo KR-211FH 2.4GHz 2-channel micro receiver is making use of KO Propo’s FHSS transmitting technology and is useable with the RF-903FH and RF-904FH modules as well as the EX-1 KIY. It features programmable failsafe, quick binding and dimensions of 29.3×24.4x16mm and a weight of 7.8g.
Source: Robitronic [robitronic.com]