The 6434 Sleeve Height/Counterbore Gage by Central Tools allows the user to properly measure the depth of cylinder sleeves relative to the block surface.It can also be used to determine top dead center and measure counterbore as well.Includes both a flat and pointed contact.Hardened base is precision ground for accuracy.Indicator has a 1” range and is graduated in .001”.Indicator can be rotated to aid in viewing from any angle.Made in USA.