Steel bondage
From wipipedia.org

Steel Bondage involves metal restraints, usually made of iron or steel, such as Handcuffs or Shackles. Due to the unforgiving nature of metal versus flesh, steel bondage has it's own set of safety issues.
External links
- The Ten Commandments of Steel Bondage by Harold Cox and David Stein (1982)
- LOCKED-SHUT: 10 Questions for Steel Bondage Scenes by Tanos (2004)