Metal handcuffs are restraint devices typically made of steel or other durable metals. They consist of two circular loops connected by a chain or hinge, designed to secure a person's wrists together. Handcuffs are commonly used by law enforcement officers to restrain individuals during arrests or transport. These devices are often equipped with a locking mechanism that prevents the wearer from easily removing them. Metal handcuffs are preferred for their strength and reliability, making them a standard tool in policing and security. They are part of a broader category of restraints, which can include items like plastic handcuffs and leg shackles.