The slaving collar was designed to keep prisoners and slaves in line. The collar consisted of a neck brace that was often linked to chains or cables. It sometimes featured shock panels to shock an unruly captive, in which case it was referred to as a shock collar. Some types of slave collars would also be designed to explode if one attempted to improperly remove it, or be detonated by transmiter if the slave attempted to escape.
The Zygerrians used them to keep slaves under control.[1]
At the time of the Galactic Civil War, captured Wookiees were usually forced into chain groups with a slaving collar around their necks by Trandoshan slavers. Usually the lowest ranking member of the slaver patrol had to place these collars around the Wookiees' necks — a very dangerous job.[2]