Heli-Coil inserts are available in thread repair kits and sets for repairing tapped holes which have been stripped or damaged due to wear, corrosion and over-torque. They are available in inch, metric, spark plug and pipe thread series. All kits have a quantity of inserts, the proper size drill, high speed steel Heli-Coil tap and an installation tool. The Professional Kits also includes a tang removal tool and quantities of three lengths of inserts.