Performance Tool  W80529 Combination Tune-Up Feeler Gauge Features 12 straight steel blades, 6 straight brass blades, 6 wire test loops, and electrode adjuster Steel: .010 to .026" and .254 to .660 mm. Brass: .006 to .016" and .152 to .406 mm. Loops: .025 to .045" Country of origin: China