1, this module is in line with international safety standard, control areas and load area have the isolation groove; 2, USES the loose quality goods relay; 3, have power and relay operation instructions, and bright, disconnect the dawn; 4, signal input signal, the public end and will often start conduction; 5, can be used as a microcontroller development board module, can be used as a home appliance control; 6, dc or ac signal control, can control 220 v ac load; 7 and one often opened a normally closed contact; 8, blue KF301 terminal line more convenient.