<p>
In today's show Ken recommends a fairly affordable tool for measuring all sorts of dimensions.
</p>

<img src="/eps/hpr3534/Vernier_caliper.svg.png" alt="An image of a Vernier caliper" />

<p>
From <a href="https://en.wikipedia.org/wiki/Calipers#Vernier_caliper">Wikipedia</a>
</p>

<ol>

<li>Outside large jaws: used to measure external diameter of an object (like a hollow cylinder) or width of an object (like a rod), diameter of an object (like a sphere).</li>
<li>Inside small jaws: used to measure the internal diameter of an object (like a hollow cylinder or pipe).</li>
<li>Depth probe/rod: used to measure depths of an object (like a small beaker) or a hole.</li>
<li>Main scale (Metric): marked every millimeter and helps to measure length correct up to 1 mm.</li>
<li>Main scale (Imperial): marked in inches and fractions.</li>
<li>Vernier scale (Metric) gives interpolated measurements to 0.1 mm or better.</li>
<li>Vernier scale (Imperial) gives interpolated measurements in fractions of an inch.</li>
<li>Retainer: used to block movable part to allow the easy transferring of a measurement.</li>
</ol>
