These Sets Represent The Ultimate In Layout Versatility. The Incra Pro Rule Sets Include Not Only A Marking Rule And Bend Rule, But The Standard T-Rule Is Also Upgraded To The Pro T-Rule. In Addition To Inca's Patented Marking Holes At Every 1/16-Inch, 1/32-Inch, And 1/64-Inch, The Pro T-Rules Go Two Steps Beyond Our Standard T-Rules By Including Marking Holes At An Incredible 1/100-Inch (0.010-Inch) Spacing And Also A Metric Scale With Marking Holes On 0.5Mm Spacing. Available In 6â€/150Mm Or 12â€/300Mm Lengths, And An Incra 0.5Mm Precision Mechanical Pencil Is Free In Each Set.