【Built-in Ball Bearing Design】With a load-bearing capacity of up to 330 lbs, this hinge ensures smooth and quiet operation even for fully loaded bookcase doors. Even when your bookshelf is packed with heavy books, the door opens effortlessly and quietly, with no strain or squeaks. 【Flat Base Convenience】Skip the hassle of complex installations. The upgraded flat-base design means no bottom slot is needed. Just align, screw in, and you’re done — saving you time and effort. 【Why Choose it】By mounting at the top, the hinge evenly distributes the door’s weight, providing enhanced stability and reducing the risk of sagging. It’s a reliable choice for heavy doors like bookcase doors, pantry doors, or hidden passageways. 【Easier Installation】: We provide detailed instructions, diagrams and measurements for the placement of the materials to ensure accuracy and quality. You can also watch our step by step video tutorial for easy installation. This will save you time and hassle and give you a satisfying result. 【Excellent Service】:To ensure quality, each of our pivot hinges undergoes strict quality control before leaving our factory. If you have any questions about our pivot hinges, please feel free to contact us, we will reply you within 24 hours and give you a satisfactory solution! 330 Lbs Pivot Hinge + Door Ball Catch