A: one-way (5V power supply) Features of one-way type: 1 channel servo signal input, control one-way electronic switch. Max control 20A current. Only supports 5V voltage receiver, otherwise it may cause module damage. If the receiver and servo use a high-voltage system, a voltage reduction module should be added to the module before it can be used. PWM frequency: 50HZ. PWM cycle: 20MS High level: 1700US on, Less than 1300US off Size: 41x16x14mm Cable length: about 30cm Weight: about 13g Used for RC model airplane, car, boat Description of one-way type: 1. Connect: Plug the signal input cable into an idle receiver channel that corresponds to a switch on the remote controller. The power indicator be illuminated when connected to the receiver. The work indicator lights up when the switch channel is open and vice . 2. Working mode: The LED light indicates the power indicator and relay's operating status. 3. Trigger: Turn on the switch (OFF→ON) on the remote control, the green LED light turn on, and the relay start working. Application range: Remote control model launch Remote control model smoke control Weapon system control like real machine Smoke control of the model aircraft Control of remote switching systems Switch signals between two cameras Control the power conduction and disconnection of electrical equipment, such as aviation lights, searchlights, explosion lights, buzzers, etc. Control the camera shutter or switch between recording and photography modes Color: As shown Material: PC+Plastic Package Contents: 1pcs x relay Only the above package content, other products are not included. Note: Light reflection 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.