The adjustable voltage range can be really smooth and adjustable from 9V to 60V. Wide application: Suitable for DC motors up to 20A. Durable Performance: High-quality use and delicate metal shell, anti-rust, safe and easy to use. High-quality circuit board ensures stable and durable performance. Easy To Use: Easily control voltage and speed by adjustable rotary knob. This is a simple and easy to use DC motor speed controller. use with minimum size, elegant appearance and stable performance. It is made with high quality circuit board which ensures longer service life. The input voltage can be between 9V and 60V, and the output voltage is between 0 and 100% of the input voltage. This speed controller is very convenient to use. The feature is: The adjustable voltage range can be very smooth and adjustable from 9V to 60VV Wide application: suitable for DC motors up to 20A. Durable performance: using delicate and high-quality metal housing, rust-free, easy easy to use and operate. High-quality circuit board ensures stable and long-lasting performance. Easy to use: Easily control voltage and speed with the adjustable rotary knob. Specifications: Color: Silver Material: Metal Input Voltage: DC 9 -60V Output current: 0-20A Power: 1200W PWM frequency: 25KHz Adjustable speed range: 0 -100% Channel speed adjustment: Potentiometer Output voltage: linear under load Efficiency:> 90% Size: approx. 92 x 52 x 36mm/3.6 x 2.0 x 1.4in Package weight: 132g Package List: 1 x Speed Controller