Patent ID: 7913526

Claim:
A lock, comprising: a body; a shackle having a toe and a heel, the heel being retained by the body and able to rotate within the body; a first and a second locking mechanism to lock the shackle, each of the locking mechanisms being enabled to independently unlock the shackle, wherein the toe, in a locked position of the second locking mechanism, is positioned between a first level defined by a top surface of the body and a second level defined by a bottom surface of the body, the toe, and in an unlocked position of the second locking mechanism, is not positioned between the first level defined by the top surface of the body and the second level defined by the bottom surface of the body; a retaining structure having a walled section and a non-walled section, the retaining structure being movable between a first position and a second position by the first locking mechanism; and wherein when the second locking mechanism is in the locked position, when the shackle is aligned with the body and when the retaining structure is in the first position, a first part of a perimeter of the toe is surrounded by the walled section of the retaining structure and a second part of the perimeter of the toe is surrounded by the body; and wherein when the second locking mechanism is in the locked position, when the shackle is aligned with the body, and when the retaining structure is in the second position, the first part of the perimeter of the toe is not surrounded by the walled section and the shackle is free to rotate about the heel.