Starrett 0-6" Dial Fractional Caliper Hardened stainless steel bar, measuring surfaces, rack, gears, and depth rod. Specification include... White Dial, .001" graduation, .100" per revolution Yellow Outer Fractions Dial, 1/64th graduation Features include... Thumb-operated fine adjustment roll allows for one-hand use Lock screw holds the sliding jaw in position, to ensure a consistent measurement Rack teeth point down to keep foreign matter from clogging the gear, to help prevent measurement error Hardened stainless steel bar, measuring surfaces, rack, gears, and depth rod for accuracy and long life The 1202F shows measurements as fractions on the yellow outer scale with 1/64th-Inch graduations and decimal measurements on the white inner scale with 1/100th Inch graduations Sharp black graduations on the satin finished bar