Calipers

Calipers are like really fancy rulers that can measure things really precisely. They have two arms that can move closer together or further apart. When you want to measure something, you put it in between the arms of the caliper and move them up close to it. Then you can read how far apart the arms are and know exactly how big the thing is. Calipers can measure things like the length of a pencil or the thickness of a piece of paper down to the tiniest fraction of an inch. They're great tools for scientists, engineers, and anyone who needs really accurate measurements.