Also known as micrometer feeler gauge sheet or thickness, is one of measuring instruments used to test gap, a cross section of a right triangle, the hypotenuse in a scale, the use of acute sine directly represented in the shorter side of the hypotenuse,so that it can directly read out the size of the seam.
You must first remove dirt and dust feeler and the workpiece on the front feeler use. Available one or several ply inserted using the gap to find a little dragging appropriate. When measuring action to light, it does not allow a hard plug. Do not allow measurement of high temperature parts.