If you play with locks a little you certainly found out that some don't
open with standard lockpicking tools. The lock shown below first appeared
to be pretty hard to open.
This is the kind of cheap lock you should never buy.
But then I looked at the key a little further and I modified it like in the
picture below. You can see that I removed all the teeth except the last one.
The original key and the modified key.
You can see in this picture that inside the lock there are several metal
plates. The trick is that you can now insert the modified key between
any two metal plates and turn to push on the pins until the lock open,
and this will work in any lock of this kind because when you push on a
pint it does not come back in place when you stop applying pressure like
in a normal pin tumbler lock. This allow you to press on each pin separately and
at one point the lock will open.
The interior of the lock.
In this particular lock, I found that there is only two pins that I need
to press before it opens. They are located inside the lock as shown in
the picture below.
This is the two points up to where you should insert the modified key.
That's all. Now my only advice is don't buy this kind of lock, because it's really too easy to open.