Heli-Coil inserts are packaged according to thread size for easy handling and display. The length of the inserts in inch and metric packages is 1–1/2 times the diameter of the bolt. This provides sufficient strength in most applications. Spark plug hole inserts are packaged in lengths corresponding to the various spark plug reaches. For shorter or longer lengths and volume applications.
Heli-Coil manufactures various styles of installation tools based on usage requirements. Automotive Aftermarket repairs fall under the less frequent to medium frequency use requiring basic threaded mandrel and a threaded mandrel with non-captive prewinder designs.