A shim is a tool that is used to
bypass
Bypass may refer to:
* Bypass (road), a road that avoids a built-up area (not to be confused with passing lane)
* Flood bypass of a river
Science and technology Medicine
* Bypass surgery, a class of surgeries including for example:
** Heart bypas ...
padlocks. It works by retracting the spring-loaded catch that restrains the shackle.
Like other types of
lockpicks, shims can be professionally made or improvised out of easily available materials like aluminum cans.
Higher security padlocks typically use techniques that make shimming impossible. The most common being the use of ball bearings instead of a spring-loaded catch, noticeable because the indentations on the shackle are round instead of wedge-shaped.
Locksmithing
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