Unpacking the lock
As the number combination lock is dissected a very interesting picture comes in sight. There are no screws in the number combination lock, all that is used to tightly pack the structure is strong mechanical hooks that binds the material together. The image below shows the rear design of the casing.
This part shows clearly that there is no space for screws. Apart from that, three rectangular slots are cut out in the metal body for positioning of the disk in the comfort zone of viewers eye.
Digging deeper into the number lock and opening the metal/alloy casing of the number lock the image below shows the arrangement of different parts inside the casing. Once again there are no screws used anywhere. Every part has been crafted to perfection and every single mark on any of the parts has an importance in the mechanism of operation of the number lock.