For precision work, you can't beat a Shinwa steel rule.

This 300mm (about 12 inch) rule is made from high-quality stainless steel that's precision ground and polished to an incredibly smooth edge – perfect for guiding a pencil or scribe without catching.

The markings are deeply etched and then filled with black chrome plating, so they're easy to read, resistant to wear, and have a low-glare finish.
It even comes with a clever stainless steel 'ruler stop' that slides along the rule.

You can hook this stop over the edge of a workpiece to use as a depth gauge, to mark a repeat measurement, or to simply keep the rule from slipping.

This rule is manufactured to the strict Japanese Industrial Standard (JIS) B7516 Grade 1, which governs materials, heat treatment, and accuracy.
A top-tier tool for machinists, woodworkers, engineers, and serious hobbyists who demand accuracy.