This may be found in the Harry Anderson Book and the entire routine involves other properties you may already have Trick Wallet, Thumbtip and the like.  What you have is a Regular Set of Handcuffs, Two Halves of Handcuffs and a Single Cuff that is made like a Key Ring.  Included also are keys for the handcuffs and 6 pages of instructions and if you don't do the full routine you have the Special Handcuffs that I am sure other ideas will present themselves.  Condition very fine.