A very common way of attacking a padlock is to drill down the centre of the pin tumbler cylinder. This destroys the pins and alows the cylinder to be turned.
A paracentric keyway has a very contoured shape, you can see in the picture on the right that the shape overlaps the centre line. All this is done to make it difficult to get lock picking tools into the cylinder.
Kasp™ padlocks feature paracentric keyways.
Hasp and Staple
A hasp and staple is the fitting attached to a door, gate, toolbox etc, through which a padlock is attached, the staple is hardened to resist cutting attack and the screws holding the staple down are completely concealed.
It is very important that the security rating of the padlock and hasp and staple are matched, otherwise you get a 'weakest link' security risk.
A very good anti-drill measure, offered on the Kasp™ 160 series, is a slotted, hardened steel disk that sits over the key entry to the cylinder. This makes it very difficult to get to the pins with the drill.
Even better is the key way on the Kasp™ 190 series padlock. In addition to the spinning disk this lock also has a hardened fixed plate specially designed to grab and break the drill.