Features: Handheld Coil On Plug fast-ignition tester, battery powered, with stable and professional-performance. Designed to easily and quickly determine whether the COP produces the proper spark for the plug. It works by receiving the signal from the secondary ignition coil, and the test result is accurate and reliable. Once the signal is received, the tester will determine whether the COP produces the correct amount of voltage-and arc-duration. If the voltage-is correct, the tester will beep-and the red LED indicator will flash; if the arc-duration is correct, the green LED will also flash. Specifications: Material:Plastic Size:As Picture Shown Note: .Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. .Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thanks for your understandings. Package includes: 1x Ignition System Tester