Features: This product is a 4-channel flip-flop latch relay and low pulse trigger module. It is a bistable (self-locking) relay module. Trigger once, the relay pulls and holds; trigger again, the relay releases and holds. Use 1: By default, the relay is released. Press the trigger button, the relay pulls in; press again, the relay releases; press a third time, the relay pulls in, and so on. Use 2: By default, the relay is released. MCU outputs a low pulse (0.3–1 second), the relay pulls in; another low pulse causes the relay to release; a third low pulse causes the relay to pull in, and so on. Typical applications: Automotive electronics, motors, LED lighting, smart home systems, emergency lighting, MCU development boards, toy cars. Constructed with high-quality electronic components and precision manufacturing for durability. Specifications: - Working voltage: DC 5V - Working current: 1 relay 70mA; 2 relays 140mA; 3 relays 210mA; 4 relays 280mA - Standby current: 4µA - Load current: AC 250V / 10A, DC 30V / 10A - Trigger mode: Low pulse trigger - Size: 6.5 x 4.3 cm (2.6 x 1.7 in) - Weight: Approx. 53g (1.9 oz) 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: - NO: Normally open relay interface - COM: Common relay interface - NC: Normally closed relay interface Package list: 1 x Self-locking Relay Module