These types of slide rails have hidden slide rails, riding rails and other types of slide rails, which are medium-to-high-grade slide rails. The gear structure is used to make the slide rails very smooth and synchronized. Such slide rails also have buffer closure or compression rebound. The opening function is mostly used in medium and high-grade furniture. Because the price is relatively expensive, it is rare in modern furniture, so it is not as popular as steel ball slides. This kind of slide is the future trend.