A game mechanic by which players can be restrained without actually typing them up (which could prove dangerous). From the Accelerant core rules:

"Shackles are a prop that binds the wrists or legs of a character. An in game lock is affixed to each prop to represent the locking mechanism of that prop. The prop must be loose enough to remain comfortable and, for safety, the player must be able to easily remove the prop if an out of game need arises."

"Shackles can only be placed on a helpless or willing character if the lock is open. You place the shackle prop on the helpless or willing target and close the lock. Shackles placed on the arm restrict movement and make it impossible to use any skill that requires that the arms must be free, including using weapons, using packet attacks, and using First Aid. You may use a skill that allows you to attempt to open a game lock on your own shackles. Shackles placed on the legs make it impossible to run and restrict movement to the extent of the shackles. A prop placed on the ankles must be constructed to allow the player to stand and walk slowly."

"Shackles can be removed by opening the lock or by using an appropriate skill to remove them. Each game will have a skill assigned to destroy and remove shackles by taking a minute and using the appropriate props and role playing. Skills that allow a character to slip out of bonds are possible as well."