Heli-Coil 5521-1 #12-24 wire thread repair kit
Check compatibility
5521-1 is the Heli-Coil coarse #12-24 repair kit. The manufacturer chart identifies the 0.324-inch insert length for the kit, separate from the 24-TPI thread.
Questions before ordering
What is the installed length listed for the kit's insert?
The manufacturer chart lists 0.324 inch for the #12-24 kit. Compare the depth of the opening before choosing a refill.