These Darby handcuffs are made of nickel plated steel and have only one locking position. High quality construction and finish. Unlike most other Darby restraints the key is a male one, which is known as "Sheffield pattern". The bow can not "snap closed", so you need the key to close the handcuffs, which makes them very secure.

 

The inner dimensions of the cuffs are:

Lady: 2 7/16in x 2 1/16in   circumference: 7 3/8in   weight: 16oz
Men: 2 11/16in x 2 3/16in   circumference: 8 1/4in    weight: 18oz