Straight leaves. Leaves made of finest tempered-steel, carefully finished to correct thickness, individually tested and marked with thickness. Locking device on most gages. Leaves easily removed or replaced. Rugged, substantial steel case protects leaves. Thickness marked on leaf. Locking device securely locks 1 or more leaves in position. For adjusting tappets, spark plugs, distributor points, checking bearing clearances and gear play, fitting pistons, rings and pins, and gaging narrow slots.