Heat and expand frozen, rusted, or thread-lock compound nuts with out the collateral damage from a flame. Uses high frequency magnetic fields to heat metal and only metal, induction heat. Operates on 120 volts/1000 watts of power!. Faster and Safer than a torch Variety coil pack for the Mini-Ductor replaces the original coils that come with the Mini-Ductor kit, which include: . 1(MD99-601) 7/8" preformed coil. 1(MD99-602) U-form coil. 1(MD99-603) Bearing Buddy coil.