Sports Parts Inc. Spark Plug Indexing Washer Kit

Inexpensive and Effective! Indexed spark plugs align the open end of the electrodetoward the intake port, the hottest part of the flame meets the new fuel charge for a performancegain, increased fuel mileage and plug life.You simply mark the electrode side of the plug with a marker on the porcelain, then shimthe plugs with the washers to align the electrodes toward the intake ports.