After hollow aluminum tube handles precision machining, grinding, polishing process. Base within the structural design, assembly 3. 0 mm thick and strong resilience of the spring, after tens of thousands of test resilience. Base materials of manufacture, options have metal plates or # 304 stainless steel sheet, iron-plated white base color or color zinc zinc. Single sticks or pumping easy to install, with no screw heads exposed dark, exquisite appearance, high-grade. Suitable for fire doors, ordinary steel doors, doors, remove doors, aluminum door installation. Factory rigorous testing, reasonable structure, strong durable