ECO-WORTHY Single Axis Solar Tracker Kit: 12 Volt 18 Inch 18'' Stroke Linear Actuator & Track Controller with Light Sensor 12V 18 Inch Linear Actuator with Track Controller Kit, Perfect for Solar Panel Tracking System. The Linear Actuator is Widely Used in Number of Industries, such as Electric power, Machinery, Metallurgy, Petroleum, Chemical Industry, Transportation, Lifting, Construction and so on. The Tracking Controller Kit has Automatical Detection System. Red and Green LED Display Easy for Check Working Station. Over Current Protection and Wrong Battery Pole Connection Protection. Stainless Steel Sensor Anti Water and Rust. The Sensitivity of Light can be Adjustable.