Features: Digital display DC voltage detection with relay output control. DC 6–80V relay interface board includes 2 buttons for easy operation. Clear LED display allows convenient voltage monitoring. Adjustable voltage detection range: DC 0–99.9V. Relay activates when measured voltage falls below lower limit or exceeds upper limit. Suitable for voltage detection switching, battery over-voltage/under-voltage protection, or discharge monitoring. Includes protective cover. Specifications: Material: PCB + ABS Working Voltage: DC 6–80V Voltage Detection Range: DC 0–99.9V Accuracy: ±0.1V Working Current: 8mA/24V (relay open, LED off: approx. 4mA/24V); 58mA/24V (relay closed) Switching Function: Normally open (NO) / Normally closed (NC) Contact Rating: NO: 30A/250V AC or 30A/30V DC; NC: 20A/250V AC or 20A/30V DC Note: Due to high-voltage DC arcing risks, for loads above DC 60V, current must not exceed 10A. Contact Resistance: 100mΩ (1A, 6VDC) Mechanical Durability: 10 million operations Electrical Durability: >100,000 cycles (20A, 250VAC) Operating Temperature: -40°C to 85°C Item Size: 9.4 x 5.2 x 3cm / 3.7 x 2.05 x 1.18in Package Size: 9.5 x 6 x 3cm / 3.74 x 2.36 x 1.18in Package Weight: 85g / 3oz Package Contents: 1 x Relay Switch Controller