Superior Anti-Interference- With pseudo random FHSS algorithm, the Radiolink R8FG 8-Channel Receiver has extraordinary anti-interference ability, and distance up to 1900 feet (600 meters). Go and enjoy the freest RC experience! Latest V2.1 Version Radiolink R8FG Receiver- 3ms* Response, servo speed can be selected from 14ms, 4ms, and 3ms. 14ms is suggested selected if connect with the analog servo, while 4ms or 3ms is suggested selected if connect with the digital servo. (*Attention: It is necessary to update the firmware of RC8X to V1.1.5 or above, and then select FHSS V2 protocol to display this option)