Review on 1221-308 Thread Repair Kit - Enhance Your Thread Repair with Thread Kits by Runbi Alvarez

cheaper than the spiral coil, essentially the same product! came with a bundle of coils, a tap and a tool to screw the coil into place. I used this to fix broken bolt threads on the rear hub of an old Vespa (cast aluminum). Stainless steel coils. You need to purchase the required 21/64" drill bit yourself. I have this Bosch drill: http://www.amazon.com/Bosch-CO2148-64-Inch-Cobalt-Jobber/dp/B000AEQQX6/