0.2mm , you can choose the detail size feeler gauge which more suitable for your use. Used for house inspection, engineering inspection,home DIY and professional use etc. This feeler gauge can be used to measure widths, clearance and also flatness deviation. In order to measure flatness deviation, you need to use it with a level ruler. Designed with a vernier which can help you to read the measuring result easily., Manufacturer: Akfldms