The receiver can normally receive the transmitter signal, push the rocker to the failsafe set, long the receiver bind button, the blue light flashes quickly several times and then always bright, failsafe settings is successful. size:11 x 25 x 3mm colour:black Material:PCB Package Contents: 3 x FS2A 4CH AFHDS 2A Mini Compatible Receiver 3 x parts Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.