Features: and high quality. With stepless speed control knob, it can be adjusted or turned off. Adjustment range: 25% to 100% (can be switched off). Constructed with pure copper thickened wire for improved safety and stability. Suitable for dimming light bulbs, adjusting airflow in aeration pumps, controlling water flow in water pumps, regulating fan speed, adjusting heat output on heating plates, managing power in equipment, and controlling motor speed. Specifications: Material: Electronic Component Weight: 15g Size: 50x19x23mm (1.97x0.75x0.91 inches) Color: Black Working Voltage: 10-14V Control Current: 1-4A Adjustment Range: 25%-100% Rated Current: 4A Note: 1. Please allow 1-2cm measurement deviation due to manual measurement. Ensure you are comfortable with this before ordering. 2. Due to differences in monitor displays, the image may not reflect the actual color of the item. Package Includes: 1 x Speed Controller