Key benefits — why you need this controller Precise, efficient speed control for low-voltage DC devices using PWM, improving performance and reducing wear compared with uncontrolled full-voltage operation. Built-in protection (resettable fuse) and power indicator increase reliability and make the controller safer to use with small motors and pumps. Simple, single-knob operation with on/off switch makes adjustments fast and intuitive without extra equipment. Main features and specifications Function: PWM DC motor speed controller with potentiometer that includes a switch function and a power-on indicator LED. Input voltage: operates from DC 1.8 V to 15 V; particularly suitable for devices commonly powered in the DC 1.8 V–12 V range. Output capability: maximum continuous output current 2 A; maximum continuous output power up to 30 W. Control range: duty cycle adjustable from 0% to 100% for full-range speed control. Protection: uses a resettable 2 A self-restoring fuse — if current is excessive the fuse disconnects and automatically resets after the unit cools. Low-voltage suitability: designed for ultra-low-voltage DC motors and small DC loads. Compatibility and practicality Works with small DC motors, low-voltage fans, aquarium oxygen pumps and similar DC devices within the stated voltage/current limits. Ideal for retrofitting or adding variable speed control to existing low-voltage equipment without replacing the motor or power supply. Typical use scenarios Aquarium oxygen pump: fine-tune airflow to match tank conditions while protecting the pump from overloads. Small cooling fan: adjust fan speed quietly and efficiently in electronics enclosures or hobby projects. Low-voltage DC motor applications: control the speed of small conveyor drives, model machinery, or DIY devices operating within the specified voltage/current range. Notes and safe-use reminders Do not exceed the maximum continuous current (2 A) or power (30 W). The built-in resettable fuse will protect the controller but repeated overloads can stress connected equipment. Confirm your device voltage falls within the controller’s operating range (recommended compatibility: 1.8 V–12 V devices; controller input up to 15 V).