The set includes: 4pcs spring bolt lock with 16pcs fixing screws. Material: High quality aluminum alloy material, thick base, rust-proof and brittle, safe and reliable. Size: The overall size of the automatic door lock is about 57mm x 43.7mm, the color is black; The screw size is 16 x 4mm. Features: Easy installation, choose the installation location, drill holes and tighten the screws; Built-in automatic spring, stretchable and soft, just pull, loosen and rebound automatically without hurting your hands. Wide range of applications: Widely used in various doors and windows, toolboxes, storage cabinets, etc. to improve their safety. Note: The data are all measured manually. Please allow an error of 1-3cm. Due to the difference between light and display, there is a certain color difference, which is subject to the actual object received