This 3 Inch 5 Lever Key Deadlock by Atlantic has been designed with a Satin Chrome, creating a refined and sophisticated look. Atlantic's deadlock comes predrilled, saving you time and ensuring a quick and easy installation process. What is a dead lock? Also known as a dead bolt, dead locks are a type of door locking mechanism which can only be opened and closed with the turning of a compatible key. Dead locks do not include a latch, meaning the door will not remain closed when unlocked. Suitable for both external and internal doors, dead locks are often installed as a secondary security measure for external doors to work in conjunction with a standard door knob or backplate lock. Features & Benefits BS3621 British Standard BS EN 12209 Matching woodscrews included Complete with dust box Product Specification Material: Plated on Pressed Steel Lockcase Depth: 75mm / 3" Backset: 57mm Face Plate: 125mm x 25mm Finish: Satin Chrome Weight: 0.5kg