Keysert^® inserts are solid, one-piece, key-locking inserts used to repair damaged threads or for use in original equipment. The Keysert^® locking keys provide a positive mechanical lock that prevents rotation due to vibration or torsion. Keysert^® inserts are available in carbon or stainless steel in both inch and metric series. Thinwall, heavy-duty, extra heavy-duty and solid insert styles are available separately or in kits containing a range of sizes.