**For new PRO series tool for daily use, please see eBay item number:155646637695

Stop scratching your cylinder bore with metal ring squaring tools!

This printed plastic tool is custom made for your cylinder bore to safely and squarely place piston rings 15mm into the bore for easy and repeatable measuring. Tall sizes are available!

The tool is notched to allow *some* yield for bores up to 1mm smaller than what the tool is labeled for but generally you will have to order the exact size of the cylinder bore you are working on.

For a custom size not listed, please choose the closest size in the listing and put a note at checkout specifying what size you need.

This is the latest v3 with more accuracy for a better fit, chamfered edges, and made from galaxy black PETG material.

First Class Mail shipping is always free!