[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 includes a switch function to control motor speed from 0% to 100%. Features an adjustable potentiometer with a flexible cable that can be detached. Cable length is 15CM. [30A Fuse]: Includes a 30A fuse to protect against short circuits. Provides double protection for your motor and motor speed controller. [Note 1]: Input power supply must be greater than 1.5 times the motor's rated power for proper operation. Input voltage must match the motor's rated voltage. [Note 2]: If used with a children's car that 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 exceed 1.5 times the motor's rated power. Input voltage must match the motor's rated voltage. For Children's Car Modification: The output end of the speed controller can be connected to a forward and reverse switch to enable forward and reverse control. If the children's car has a forward and reverse circuit regulator, connect the speed controller between the power supply and the regulator to prevent damage. Specification: DC Motor Speed Controller 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: 2.5mm / 0.4cm diameter / 12AWG Wire Length: 26cm (total length including 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 actual item. Measurement may vary by +/- 1-3cm.