• Set for testing cylinder compression pressure on gasoline engines

• Provided with mostly common used spark plug adapters, sizes are M10 × 1.00, M12 × 1.25, M14 × 1.25, M18 × 1.50

• Includes aluminum test tubes, fitting in-line and V-shape engines

• Rubber tube equipped with an enhance locking design, preventing the adapter from being left on the spark plug hole when disconnecting the rubber tube