1. Press and hold the key on the receiver and connect the power to the receiver. The blue light on the receiver flashing, into binding mode.2. Set the transmitter into mode (confirmed AFHDS 2A protocol). After into mode, the receiver light changes from flashing to slow flash.3. Transmitter out of mode, then the receiver blue light becomes bright. Indicates that the signal received is successful.Failsafe :The receiver can normally receive the transmitter signal, push the rocker to the failsafe set, long press the receiver button, the blue light flashes quickly several and then always bright, failsafe is successful.size:11*25*3mmcolour:blackMaterial:PCBPackage Contents:1 * FS2A 4CH AFHDS 2A Mini Compatible Receiver1 * partsOnly 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.