Features: Digital display for DC voltage detection with relay output control. DC 6-80V relay interface board with 2 buttons for easy operation. Clear LED display for convenient voltage reading. Adjustable voltage detection range: DC 0-99.9V. Relay activates when measured voltage is below lower limit or above upper limit. Suitable for voltage detection switch, battery over/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 approximately 4mA/24V); 58mA/24V (relay closed) One set of changeover contacts (normally open/normally closed, NO/NC) Contact Load: NO: 30A/250V AC or 30A/30V DC; NC: 20A/250V AC or 20A/30V DC Note: Due to high voltage DC arc risks, for loads above DC60V, current must be less than 10A. Contact Resistance: ≤100mΩ (1A, 6VDC) Mechanical Durability: 10 million cycles Electrical Durability: >100,000 cycles (20A-250VAC) Operating Temperature: -40°C to 85°C Product Dimensions: 9.4 x 5.2 x 3cm / 3.7 x 2.05 x 1.18in Package Dimensions: 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