Detail 4 CHANNEL RELAY MODULE RED 5V high quality keyes brand mark
KEYES HIGH QUALITY MARK Description: 1.The input signal can be 3.3 V 5 V
2.Are low level effective. Support 3.3V 5 V 3It has jump line. Can set high and low level 4.The power source and the relay system power can be divided 5.A set of jump cap. Jump hat off. Can separate the power supply 6.Only one way of high level can be triggered