1000mm - 39-1/4" Spring-Tempered Steel Rule with Millimeter & Inch Graduations, 32nds & 1/2mm on One Side; 64ths & mm on Reverse. The Starrett 1000mm - 39-1/4" Spring-Tempered Steel Rule with Millimeter and Inch Graduation features a satin chrome finish. Graduations includes 32nds and 1/2mm on one side; 64ths and mm on reverse. 1000mm (39 1/4"), No. 36 Grad reverse.