Hose Attachment with 14mm Spark Plug Hole Adapter Note: For best results use an air compressor with at least 120 PSI output.JEGS 80520 Dual Gauge Leak-Down Tester is used to pinpoint power-robbing leakage in the piston bore, rings, valves, head gaskets, or to set fuel injector barrel valves. The adjustable regulator provides accurate readings with varying air supply. Includes hi-tech shockproof gauges tested and matched to 1/4 PSI. and a black anodized manifold body. For use in applications...