FLEX-CUF Restraints First Introduced in 1965, FLEX-CUF remain the leading disposable restraints used by law enforcement. That's because officers have come to rely on its extraordinary strength. The Strength Barb System contained within the FLEX-CUF head makes it virtually pick-proof. In addition, these flex cuffs are fabricated from materials specifically designed to prevent injuries. Nylon construction offers dimensional stability as well as flexibility. And a smooth inside surface, combined with rounded edges, minimizes the chance of abrasion or tissue injury. Individual restraints provide maximum containment of the wrist, arm, leg or ankle. Multiple configurations make FLEX-CUF the most versatile restraint available. FLEX-CUF disposable restraints reduce the risk of escape from the crime scene or designated containment area.