Performance Tool W162C Spark Plug Gauge & Gap Tool SAE Sizes: .020, .025, .028, .030, .032, .035 and .040" Metric Sizes: .50, .63, .71, .76, .81, .89, 1.00 mm 7 durable round wire blades in decimal and metric sizes. For use with newer autos with high energy engines. Lifetime warranty