Custom 2 piece rod bolt stretch gauge kit save engine builder time for faster assembly. Now the builder has gauge A for tang side of rod and gauge B for non tang side. This speeds up assembly time and accuracy so one gauge per bolt free length for a zero setting. Both are CNC machined body from 6061 aluminum with black anodized finish. Dial indicators are AGD 2 reads in .0005″ increments, upgrade with high tension spring for max preload and unit is fully adjustable. Complete with a heavy-duty blow molded black hard storage case with foam cut out insert to protect these gauges. Please e-mail us if you have any questions.