How to Read a Metric Feeler Gauge
- 1). Remove a blade from the feeler gauge.
- 2). Look for a measurement value stamped on the blade. The measurement on metric feeler gauges is typically to hundredths or thousandths of a millimeter and signified by an "mm" stamp next to the measurement.
- 3). Convert the number to its English counterpart if necessary. Multiply the millimeter value by 25.4 to determine the size of the blade in inches.
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