Features: This product is a 4 channel flip-flop latch relay, and low pulse trigger module. This is a bistable (self-locking) relay module,Trigger once, the relay pull (and holds);Trigger again, the relay releases (and holds). USE 1:By default, the relay is release, press the trigger button, the relay pull, press again, the relay release, the third press, the relay pull, and so on. USE 2:By default, the relay is release, MCU output low-pulse(0.3-1seconds), the relay pull, low-pulse again, the relay release, the third low-pulse, the relay pull, and so on. Typical applications: Automotive electronics, Motor, LED, Smart Home, Emergency lighting, MCU development board, Toy car. Adopted of high quality electronic components, and precision process, ensure for the durability. Specification: Working voltage: DC 5V Working current: 1 relay 70MA; 2 relay 140MA;3 relay 210MA;4 relay 280MA Standby current: 4UA Load current: AC 250V / 10A, DC 30V / 10A Trigger mode: Low pulse trigger Size: 6.5*4.3cm/2.6*1.7in Weight: Approx.53g/1.9oz Module interface: 5V: positive power supply (VCC) G: negative power supply (GND) T1: Trigger port 1 T2: Trigger port 2 T3 : Trigger port 3 T4: Trigger port 4 Relay outputs: 1. NO: normally open relay interface 2. COM: Common Interface Relays 3. NC: normally closed relay interface Package list: 1 x Self-locking Relay Module