DIY Frequently Asked Questions / Folding Rule')">
Measuring device consisting of 6″ to 8″ hardwood, steel or aluminum lengths connected by spring joints that unfold for measuring distances.
Some models include an extension slide for measuring closed-in areas such as doorways and window frames where a regular folding rule will not work. The rule is unfolded as far as possible, then the slide is extended and its measurement added to the overall measurement for a total measurement reading.
Different models are designed for specific measuring needs of masons, engineers, carpenters and plumbers.