ADD-ON KITS ONLY PROVIDE THE NECESSARY TOOLING TO CONVERT TO BIG-SERT You must have the original kit. What is Included: Drill, Tap, Bushing, line pin, Inserts and dowels. Second repair after a failed coil style insert. Kit includes 10 inserts of  the  P/n 37004 Extra head alignment dowels J-42385-508BS 2 are included in the kit.  Tool setup video here.