This tool is used to measure the inside diameter of the cylinder liner. The gage set comes with sufficient mandrels to measure from 6" to 12 1/8" diameter. The long shank allows for readings to be taken along the whole length of the GE liner.
This tool should be used with T10310 Gage and micrometer standard to establish the exact 9.000" reference diameter. The liner bore gauge measures bores with an accuracy of .0001".