Tamtorque sign fixing clamps are manufactured from high strength stainless steel and have a hardened tamper resistant screw with a unique recessed seven sided socket. This means that they can only be tightened or released with a special Tamtorque screw bit. An auto locking safety buckle ensures the free end of the band is both safe and tidy. The unique safety buckle was developed especially for Tamtorque and is covered by patents in many countries. European Patent No 0891508. US Patent No 6205624. Other patents are pending.