Crescent Lufkin 6 ft. Wood Rule Brass Extends

The X46FN is a 5/8 In. x 6 Ft. Red End wood rule with 6 In. slide rule extension. It has flat, inside markings and numbering begins on the inside of rule. It is graduated to 1/16th of an inch. Slide rule runs under friction in t-slot and has stops at each end to prevent the slide from falling out.