Taper Gage measures hole and slot sizes. It is quick to use, very accurate, and is a convenient size. Very useful tool for bearing work and for gaging slots Made of quality tool steel and accurately tapered throughout entire length for quick and convenient measuring 11mm (7/16") wide by 160mm (6-1/4") long Can be used as a precision shim One side graduated from .010" to .150" in thousandths of an inch; the reverse side from 0.3mm to 4mm in one-twentieth of a mm (0.05mm)