Adapters: Connect to the corresponding sizes spark plugs on most gasoline engine includes: 14mm Brass Coated Aluminum Adapter 12mm Aluminum Adapter 10mm Aluminum Adapter Package Content: 1x Dual Gauges Assembly with 19" Hose and American Style Air Plug 1x 10" Rubber Nylon Resin Hose with 14mm Brass Coated Aluminum Adapter 1x 10mm Aluminum Adapter with O-ring 1x 12mm Aluminum Adapter with O-ring 1x Detailed Instruction 1x Customized Blow Molding Case Note: 1. Please wear gloves and goggles when use. 2. This cylinder leakage test kit should be used by professional or under the guidance of a professional. 3. Always refer to equipment manufacturer's operation instruction, compare to the manufacturer's recommended readings. 4. Select neutral (or "park" if automatic transmission) and keep hands clear of the engine as engine rotation may occur when using this tool. The ignition MUST BE turned off. 5. Turn regulator knob fully anticlockwise before connecting to compressed air. 6. Require an air pressure of 45 to 100psi. Ensure the air supply is clean and does not exceed the pressure quoted. 7. Unscrew the adapter after the cylinder is cooled to prevent the hose from softening and not driving the adapter to rotate together. 8. The test can only be carried out after the engine reaches normal temperature. 9. If the threads do not match, do not twist the hose forcefully. 10. Please refer to the instruction for more details before the operation of this leakdown detector.