[Wide Voltage]: Wide voltage input 7-70V, maximum output current 30A. Recommended power range: 12V within 250W, 24V within 350W, 48V within 450W, and 60V within 500W. [Speed Control Knob]: The knob has a switch function and can control motor speed from 0% to 100%. Includes an adjustable potentiometer with a flexible cable that can be detached. Cable length is 15cm. [30A Fuse]: This set includes a 30A fuse to protect against short circuits at the motor interface. Provides double protection for your motor and motor speed controller. [Note 1]: The input power supply must be 1.5 times the rated power of the motor for proper operation. Input voltage must match the motor's rated voltage. [Note 2]: If the children's car has a forward-reverse circuit regulator, connect the speed controller between the power supply and the forward-reverse circuit regulator. Failure to do so may damage the speed controller. Precautions: This module is a DC motor speed controller and must not be connected to AC power. Input power supply must be 1.5 times the motor’s rated power for proper operation. Input voltage must match the motor's rated voltage. Modification for Children's Car: When used in children's car modifications, connect the output end of the speed controller to a forward and reverse switch to enable forward and reverse control. If the children's car has a forward-reverse circuit regulator, install the speed controller between the power supply and the forward-reverse circuit regulator. Otherwise, the speed controller may be damaged. Specification: DC Motor Speed Controller Applicable voltage range: DC 7-70V Drive current: max 30A (Refer to recommended control power for actual usage) Recommended control power: 12V: up to 250W 24V: up to 350W 48V: up to 450W 60V: up to 500W Duty cycle adjustable range: approximately 1% - 100% PWM frequency: 12KHz Fuse: Maximum current: 30A Wire diameter: 2.5mm² / 0.4cm diameter / 12AWG Wire length: 26cm (total length including terminals 30cm) Material: ABS Color: As shown Package Contents: 1 x DC Motor Speed Controller Note: Light and display differences may cause slight color variation between the image and the actual item. Measurement allows an error of +/- 1-3cm.