Door knob surround

In short, these are two adaptor rings to allow replacing an old front door lock with a new one in aluminium framed doors.

Recently, I had to change out my front door lock. Once I removed the lock from the aluminium door, I discovered that the lock had a huge internal barrel which houses the mechanism. The mechanism converts the rotational force of twisting the handle to a horizontal force used to draw the bolt open.

However when I went to buy a replacement, I found that this kind of lock