ASP Tactical Hinged Handcuffs provide a major advance in both the design and construction of wrist restraints. Frame geometry is the result of extensive computer modeling and simulation analysis. Strength potential has been maximized through use of an interlocking, unitized frame. The cuff structure is forged from high strength stainless steel on custom built, high speed progressive dies. Each restraint is then overmolded with ordinance grade polymer under 75 tons of pressure. The lock assembly is unitized and replaceable." Features include a dual keyway accessible from both sides, a yellow indicator to alert you to double lock, and very smooth action.