How many anti-oil car window films should you add at once?

You should use about 10 to 20 ml at a time, and one bottle can be used five to ten times.

If you only clean the windshield, you can use it several times. Depending on the speed of formation of the oil film under normal urban traffic conditions, it can be cleaned every two to three months (it has a five-year warranty and contains a chelating agent which it is recommended to remove). use it two years after opening).