The Performance Tool Turbocharger System Leakage Tester, No. W89748, is designed to charge the turbo system with regulated, low-pressure shop air to find a potential leak. The tester locates air leaks in turbo system components by plugging the intake inlet and the output side of the turbo. It can also be used on cooling system hoses. Includes storage case and four pairs of stepped adapters, ranging from 1-3/8" to 3-1/2", to fit most turbo systems on cars and light trucks.