High-quality aluminum, imported alloy spring steel, durable. Through the lanterns connected to the aluminum alloy rail, to achieve suspended lamps, can make the lamp up and down the stretch. Can be bearing 2-15Kg, remote control electric stretching and manual stretching two types of optional. Length with upper and lower stroke limiter, upper and lower limit automatically stop 1.2 / 1.5 / 2 / 2.5 / 3 / 3.5 / 4 / 4.5 / 5 meters.