Padlock Shims can be used to open most padlocks. Made of a very thin spring steel, they come in several sizes to fit the contour of different lock shanks. Just insert the shim into the clearance on the outside of the shackle opposite the latchand twist to disengage the locking mechanism. Some locks may be doubled latched requiring two Padlock shims. This set of 20 shims and 4 sizes makes it easy to compromise just about any padlock.