Which description best fits a steel rule?

• A. Measures up to 300mm in length and starts with 0 on one edge
• B. Used to mark lines on metal
• C. For 'denting' metal before drilling
• D. Used to scribe arcs on metal and plastic

Answer: (A)

A steel rule is a rigid measuring tool used for accurate length measurements in metalworking and related trades. It commonly measures up to 300 mm and has a zero mark at one edge, which lets you measure from that fixed starting point and ensures readings are taken from the true edge of the workpiece. This zero origin is what makes the steel rule reliable for precision work.

The other descriptions describe tools used for marking or shaping rather than measuring. Marking lines on metal is done with a scriber, not a ruler. Denting metal before drilling uses a punch, and drawing arcs on metal or plastic is done with a compass or similar instrument.