Helically-coiled wire thread inserts (sometimes called recoils, thread repair inserts or Helocoils) are a thread strengthening precision fastening device used to repair damaged or worn threads and create high strength fastenings in softer core materials. A wire thread insert is essentially a free-running, stainless steel wire coil that is inserted into a hole with a thread that has been specially tapped to accept it. It is used to create a standard-sized, internal screw thread within the existing hole. The high performance internal thread provided is far stronger than most parent materials, and is also heat, corrosion, and wear resistant.
These wire thread inserts are made from aircraft quality A2/304 stainless steel wire that is cold worked in accordance with SAE AS 7245 (equivalent and former specifications include 18/8 Austenitic, DTD 734A, BS EN 2947, and W.NR.1.3401). Inserts have a high degree of toughness and hardness, excellent corrosion resistance, tensile strength up to 1400 N/mm², hardness of RC 43-50. Withstands a temperature range of -200°C to +325°C without detriment to its properties and withstands temperature surges up to 425°C.