Description of the module:1. The module uses authentic quality relay, normally open interfacesMaximum load: AC 250V / 10A, DC 30V / 10A;2. Use SMD isolation optocoupler, ability to drive, stable performance.Trip 5mA current.3. The operating voltage of the module 5V;4. The module can be high or low by a trigger of the jumper setting.5. The fault-tolerant design, even if the command line is case sensitive, the relay won't work;6. The power indicator (green), the flag of the State of the relay (red)Interface module:1. DC: positive supply (VCC)2. DC: power negative (GND)3. IN: control relay may be high or low levelRelay outputs:1. NO: normally open relay interface2. COM: Common interface relays3. NC: normally closed relay interfaceHigh and low level triggering options:It is low level trigger when the jumper connects to bottom pinIt is high level trigger when the jumper connects a high pincolour:blueMaterial:PCBsize:Module size: 50mm x 26mm x 18.5mm (L x W x H)Four hole mounting bolts, 3.1mm diameterPackage Contents:10 x Relay ModuleOnly the above package content, other products are not included.Note: Light shooting 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.