module relay 4ch 5v arduino

Product description:
1, the module complies with international safety standards, the control area load area the isolation groove;
2, the genuine relay Songle;
3, have the power & relay action instructions, pull bright disconnect does not shine;
4, when a signal in the signal input terminal, the common terminal and the normally start conduction;
5, microcontroller development board can be 2 as a module that can be 2 as a home appliance control;
6, the control of the DC or AC signal, can control the 220 v AC load;
7, there is a normally open and a normally closed contact.
8, blue KF301 terminals to the line of control is more work.