This is Futaba’s updated, budget‑friendly 2.4 GHz  8-channel (No Telemetry) air receiver.  It supports up to 8 PWM channels with two protocols, the S-FHSS (Second-Generation Frequency Hopping Spread Spectrum) and S.Bus, Futaba's proprietary protocol. 
 
It’s widely used in because it’s simple, reliable, and compatible with many mid‑range transmitters