The robust nickel-plated steel handcuffs from Rothco have a double lock. For people working in public safety, the handcuffs are perfect. Sturdy Steel Handcuffs with a Nickel Plate.
In order to stop the detainee from tightening the cuffs too tightly around their wrist, you can use the double lock feature. The package includes two standard police cuff keys.
Important Note: This item is prohibited from being exported and cannot be purchased for use in certain non-U.S.