So. Cal. offers premium original equipment Bosch spark plug wires as well as economy brand wires. These new Bosch plug wire are 7mm and finished for a direct replacement of your old worn out plug wires. The Bosch Opti-Layer Wire delivers the maximum voltage to your spark plugs and offers unparalleled protection against harsh engine compartment conditions. Bosch is so sure about their performance it guarantees its wires for the life of your car. These are genuine Bosch plug wires Made in USA! Sold as set.