With calibration function, the detection accuracy is higher. Put an end to the misuse of various unqualified and lubricants. Oil quality control to oil product safety. Detection of engine oil, gasoline engine oil, through the detection of oleic acid, carbon deposits and moisture and other impurities. The equipment is small in size and easy to transport. Detection system:oil quality Power supply:2x3V CR2032 button battery (included) instruct: 1. Select the type of gasoline or DSL () engine. Put down the key. Wait for 5 seconds, when the green light flashes and the red light flashes on the instrument, drop the oil into the test tank. Finally the test button to test 2. Add a few drops of lubricating oil to be tested to the instrument sensor. Don't miss the test tank. 3. and quickly release the test button. Flashes 10 times in sequence. The last indicator light indicates the quality of the lubricant. 4. LEDs 1-7 flash green, indicating that the oil quality is good. The indicator light n°8 or n°9 flashes yellow, and the oil quality is average. no.10 The LED flashes red slowly. It is recommended to replace the lubricating oil. no.10 The red LED flashes quickly, and it is recommended to start the engine Colour:Black Material:Plastic Package Contents: 1 * Oil Quality Tester Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.