Household Appliance Anion Detector Negative Oxygen Ion and Anion Concentration Detector Air Anion Measuring Instrument Air Negative Measuring Instrument Tester Meter Aeroanion Detector Negative Ions Anion Concentration Detector Auto Air Purifier OOTDTY Features: This negative tester can only measure some household appliances with negative generator, such as negative air purifier, air conditioning fan, air conditioner, which can release more than tens of thousands of high concentration negative ions. It can not test negative ions released from some ordinary natural environment and some solid ions. The tester is easy to carry and is suitable for testing high concentration sources such as various positive and negative generators, air purifiers and air conditioners. Measurement 10,000-19,990,000 cm Usage method: 1. Turn the to ON gear 2. Keep the thumb in contact with the square metal sheet of the front panel. The metal sheet on the back faces the air negative generator to be tested. The distance between the thumb and the air negative generator to be tested, the the degree of the tester, and the smaller the degree of the tester. Therefore, in order to ensure the accuracy of the measurement results, please keep the tester at appropriate distance from the air negative generator to be tested. 3.Do not-touch the square metal sheet on the back of the tester with your hands during the measurement. Otherwise, the degree will be inaccurate. 4. There is no sign in front of the degree shown. Indicates that positive ions are measured; if is displayed, negative ions are expressed. 5. Keep the machine in "off" position before each measurement. Specifications: for Shell Material: Plastics Size: 80*30*10mm/3.15*1.18*0.39" Weight: 91g Notes: 1. Due to the different and light effect, the actual color of the item might be slightly different from the color showed on the pictures. Thank you! 2. Please allow slight measuring deviation due to manual measurement. Packages: 1 X Negative Meter _x000D_