5 lever mortice deadlocks are the most common type of lock used in the UK. They are also known as BS 3621 locks, and are a legal requirement for certain types of properties, such as commercial premises and rented accommodation. Here are 4 easy ways to tell if your lock is a 5 lever mortice deadlock:
1. The lock body should be embedded into the door so that only the faceplate is visible.
2. There should be at least five levers (usually six) visible on the faceplate.
3. The keyhole will usually be oval shaped, and will have a Warding mark on either side.
4. 5 lever mortice deadlocks will usually be stamped with the BS 3621 Kitemark.