4 Channel 12V RS232 Relay Module Serial Remote Control Switch Board DB9 InterfaceInstruction: Click to openFeature:DC12V power supply (voltage range 9-13V)Standby current (all relays closed) 18MA、 1 channel "open" 50MA、 2 channel "open" 81MA、 3 channel "open" 110MA、 4 channel "open" 141MARS232 DB9 Female InterfaceRead、 opening、 closing、 self-locking、 jog、 interlocking six instructions、 to meet the vast majority of industrial occasionsRelay load voltage: DC 1-100V or AC85-265VRelay current load: Max. 10AWeight: 62 gSize: 90mm * 47mm * 19mmPackage includes:1 x 4 Channel 12V RS232 Relay