Lost letterbox key

I just thought I would share a job I was called to do today in Lockleys.  A customer had lost the key for her letterbox and needed a new one cut to the same lock as she was renting and had to provide the key when she moved.
Locksmiths usually read / decode the lock in this sort of situation.  It was a typical letterbox lock, with five cuts, each cut can have three depths.  In order to read and decode the depths I used a lock-pick to feel each of the wafers in the lock and with a bit of practice you can determine the depth of the cut, i.e. 1, 2 or 3.

Its worthy of note that I couldn’t actually see all of the wafers, I had to rely on feel alone.  Once I had the depths written down, in this case it read: 3, 2, 1, 2, 1 I was able to take a blank key and file it down to those depths by hand, put it in the lock, test to make sure it works.  I did however forget to take some photos of this process to post on here, sorry.
That should give you a little insight into just what locksmiths do.