What are oval and euro cylinders?
A. An oval cylinder has an oval shape and is used in conjunction with an oval mortice lock case. A euro cylinder is similar only it is shaped like an enlarged key hole and used in conjunction with a euro mortice lock case. The cylinder fits through your door, passing through the lock case which is mortised into the edge of the door. When using door handles with these types of locks and cylinders, you must ensure that they too have the oval or euro cut out on the back plate to allow the cylinder to pass through.
