Ruedamann aluminum door threshold ramp are made of high-quality aluminum, which is durable and prevents rust. The exterior is coated and comes in rich colors. This mobile threshold ramp has many styles to choose from. The bridge type is used when there are heights on both sides of the threshold, and the combined type can adjust the length. This portable threshold ramp can be used in a variety of situations ,e.g: shower stalls, sliding glass doors, garden sheds, curbs, and more.