Metal bondage (or device bondage) is bondage involving the use of metal apparatuses to restrain a submissive as part of BDSM activities. In contrast to the use of rope to secure a body, metal bondage normally requires careful preparation, since more extravagant devices have either to be built or bought from a specialist. The range of devices can vary significantly, from simple handcuffs or chains to specifically designed chairs or complex bar linkages.