Rules, Steel, Starrett, Individual Sizes

Starrett precision steel rules are machine-divided, not photoengraved. They are inspected to Starrett Master Standards, which are traceable to the National Institute of Standards and Technology. Graduation No. 4R are 8ths, 16ths, quick-reading 32nds and 64ths. Graduation No. 16R are Quick-reading 32nds and 64ths, aircraft quick-reading 50ths and 100ths. Graduation No. 5R are quick-reading 10ths, aircraft quick-reading 100ths, 32nds and 64ths. Graduations No. 31 are 32nds and 64ths on one side; mm and 1/2 mm on reverse. Flexible rules are 1/2" wide and 1/64" thick. Rigid rules are 3/4" wide and 3/64" thick.