3. Silent function - Our hidden door hinges are made of high-quality zinc and alloy aluminum materials, which are not only durable but also quiet in operation. The built-in gasket ensures that the door moves smoothly and quietly, enhancing the function of hidden doors or secret passages.5. Strong and durable - They are able to support doors weighing up to 177 pounds and a 180-degree opening angle, providing reliable performance for your hidden door or secret passage. The hinges are also designed to be silent and wear-resistant, providing years of trouble-free operation.1. Seamless hidden door solution - Our hidden door hinges, also known as Soss hinges or door hinge kits, provide invisible integration for your secret door or concealed door needs. The completely hidden design ensures that there are no visible hinges, creating a stylish and sophisticated look.4. Adjustable and compatible - Our hinges are designed for doors with thickness >40mm and width <1000mm. The three-dimensional adjustability of vertical 3.0mm, horizontal 2.0mm and depth 1.0mm provides flexibility and is compatible with a variety of door sizes and types.2. Easy to install - Our hidden door hinges are designed to be easy to install, suitable for DIY enthusiasts and professionals. The three-dimensional adjustability of vertical 2.5mm, horizontal 1.0mm and depth 2.5mm allows fine-tuning without disassembling the door, which is very convenient.