A belly chain is a physical restraint worn by prisoners, consisting of a chain around the waist, to which the prisoner's hands may be chained or cuffed. Sometimes the ankles are also connected by means of longer chains.
Inmate in belly chain with the arms cuffed parallel at the side
Inmate in belly chain with the arms crossed (high security restraint)
"full harness" transport restraint (detail)
Belly chain secured behind an inmate's back with a padlock
Physical restraint refers to means of purposely limiting or obstructing the freedom of a person's bodily movement.
Handcuffs and chains from wrought iron as formerly used on prisoners; Wales, 19th century (museum exhibit)
Modern chain handcuffs made of hardened steel; Hiatt 2010
Modern steel legcuffs
Iron wrist shackles with chains and padlock; Germany c. 17th century