Features Military Grade Double-Layer Circuit Board Design: Ensures exceptional durability and reliability, providing long-lasting performance even in demanding applications. Original Chip and Specially Customized Silicon Controlled Rectifier: Delivers precise and stable motor speed control, enhancing al efficiency and reducing power consumption. External Potentiometer for Easy Motor Speed Adjustment: Allows for convenient and accurate speed adjustments, providing smooth and responsive control over the motor's output. Maximum Power Up to 2000W: Capable of handling high-power applications, making it suitable for a wide range of industrial and DIY projects. Compatible with DC Brush Motor: Versatile compatibility ensures seamless integration with various DC brush motors, expanding its usability and practicality. Specification: Item Type: DC Motor Speed Controller Input voltage: DC9-55V Output Voltage: Linear under load Output Limit Current: 40A (20A for long time, pay attention to keep the module under unobstructed heat dissipation condition) Ultimate Power: 2000W Speed Control Mode: Potentiometer (linear) with switch Speed Regulation Duty Range: 0-100% Control Frequency: 25KHZ Knob Wire Length: 20cm / 7.87in Motherboard Mounting Size: 85x58x38mm / 3.35x2.28x1.5in Potentiometer Mounting Hole: 7mm / 0.28in Item Weight: 130g Item Size: 8.5x6x3.9cm / 3.35x2.36x1.54in Package Weight: 138g Package List: 1 x Motor Speed Controller 1 x Knob Cover Note: Before powering on, make sure that the positive and negative connections are correct. Do not touch the heat sink with the wiring, which may burn the circuit board. Note that this is not a power supply module. It must be connected to the motor to adjust the speed. The output of the multimeter will not change without the motor. It cannot be connected to the AC brushed motor. Package List 1 x Motor Speed Controller 1 x Knob Cover