CTA Tools A308 Offset Valve Tappet Gauge Set is designed for use when setting valve tappets and makes valve lash adjustment easy. The CTA Tools Offset Valve Tappet Gauge Set features 2-Handles and 11-Blades. Easy to use simply insert the proper offset blade on the CTA Tools Offset Valve Tappet Gauge Set to adjust intake and exhaust settings. The blades insert into the handle easily and all blades come with metric markings on all 11 sizes, ranging from 0.004 to 0.014-". California Prop 65 - Warning, This product contains chemicals known to the State of California to cause cancer, birth defects or other reproductive harm.