7/8" I.D. preformed coil for heating nuts up to 3/4". 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 Loosen seized hardware, bearings, gears, pulleys, lug nuts, inline applications, fuel tank straps, pdr applications (paintless dent repair), O2 sensors, and much more! Estimated 500 uses minimum. Heating a nut red hot will reduce the life of this coil.