Features: These mortice door bolts provide additional concealed locking point, effectively enhancing the security of your door and window. Installed near the top and bottom of door. Make from coppers, these mortice door bolts is resistant to rusts and corrosion, ensuring long terms durability. The mortice rack bolts is simple to install and use. And a standard star key (included) smoothly operates the bolt, allowing for easy opening and closing. Whether for residential or commercial use, they provide additional security by offering a locking mechanism that blends seamlessly with the door’s designs. These mortice bolts is perfect for fire door, corridors door. They not only offer security but also complement modern interior and exterior fittings. Specifications: Materials: Coppers Size: Small/L S lock cylinder inner length: about 3.50cm/1.38inch L lock cylinder inner length: about 6cm/2.36inch Package Includes: 2Pcs/set Mortice Door Bolts with Star Key note: Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. Due to difference between different monitors, the picture may not reflect the actual color.