SOLID AND DURABLE: Made of heavy-duty stainless steel with maximum corrosion resistance and durability, the concealed door hinges are designed to provide reliable support for years. PRACTICAL AND INVISIBLE: With a unique roller ball design, these 360-degree rotating door hinges provide an easy and efficient way to swing your door easily and quietly. Solid rotating door hinge with heavy-duty design and smooth bearings is almost hidden. EASY INSTALLATION: The top pivot comes with a retractable pin for quick and easy installation. The rotating concealed door hinge can be mounted on the top level of the door and attached to a hole on the door's surface. WIDE APPLICATIONS: The concealed rotating door hinges work great for swing doors, murphy doors, and much more. Excellent pivot option when the door weight load on traditional door frame hinges is a concern. BUY WITH CONFIDENCE: With a compact design and solid construction, these rotating door hinges are a nice addition to your door hardware.